Interstitial Ads: Examples, Sizes, Benchmarks & Best Practices

Interstitial ads are full-screen ads that appear at natural transition points in apps and websites — between game levels, after a form submits, when moving between content pages. The user closes the ad or taps through before continuing.

They earn the highest CTRs and CPMs of any non-rewarded format in mobile display, and Liftoff’s 2024 analysis of 602 billion ad impressions found they convert to install 30× more often than banner ads in gaming. (One naming note: Google also uses the term “intrusive interstitials” for an unrelated SEO penalty on websites — different topic, covered briefly later.)

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Now the practitioner version. We’ve built interstitial ad campaigns for brands like Netflix, Disney+, A1, Swedbank, and Sadolin, across telco, banking, streaming, and home/interior verticals. Across all of those campaigns, one pattern repeats: the difference between an interstitial that hits its predicted CPM and one that quietly underdelivers isn’t placement, isn’t targeting, isn’t even the brief. It’s the creative — how it’s rendered, how heavy it is, whether it loads fast enough to be seen, and whether it gives the user something to do with the full screen rather than just look at.

This guide is what we’ve learned shipping those campaigns. It’s written for the people who commission, build, and traffic interstitial ads — media planners, ad-ops leads, agency creative teams, brand advertisers. Everything below is about the ad format itself: what it is, when to use it, what to expect from it, and why most campaigns leave performance on the table.

What interstitial ads are (the practitioner version)

The definition is straightforward: full-screen ads at natural transition points inside an app, mobile site, or desktop site — between game levels, after submitting a form, when moving from one article to the next. Three distinctions matter when you’re briefing or trafficking the format, and the words get conflated constantly:

• Full-screen, not pop-up. A pop-up covers part of the screen during a task. An interstitial covers all of it at a transition. The user must engage or dismiss before continuing.
• Transitional, not persistent. Interstitials fire at breakpoints in a user journey — never while the user is mid-task. Banners stay on screen; interstitials interrupt and then leave.
• A format, not a creative type. An interstitial can be a static image, a short video, an interactive rich-media unit, a playable mini-experience, or a rewarded ad the user opts into. The format is “full-screen at a transition”; the creative inside it is what you commission.

Because interstitial ads fill the screen, they bypass banner blindness, and in the in-app environment they’re effectively immune to ad blockers. The result: Liftoff’s 2024 analysis of 602 billion ad impressions found that interstitial ads convert to install 30 times more often than banner ads in gaming — the single strongest format-vs-format performance gap in mobile display.

But that premium only materializes when the creative is built to deliver against it. Which is where most campaigns fall short, and what the rest of this guide is about.

See live interstitial ad examples in the NEXD Ad Gallery →

How interstitial ads work in the bid stream

Interstitial ads run in two delivery contexts. Interstitial web ads are served like any HTML5 banner — through your DSP and a standard ad server — but render full-screen between page transitions on mobile web or desktop. In-app interstitials are delivered by an SDK embedded in mobile apps (AdMob, AppLovin MAX, Unity LevelPlay, ironSource) and account for the majority of interstitial ad spend. The buying flow is the same — both run through programmatic exchanges and the OpenRTB auction described below — but in-app SDKs handle pre-caching differently, which matters for delivery.

You don’t need to implement this — your DSP and SSP handle the mechanics. But understanding what happens between “user finishes a level” and “ad renders on screen” tells you why some campaigns deliver predicted CPMs and others quietly underdeliver. An interstitial impression is an OpenRTB auction that resolves in roughly 200 milliseconds. Here’s the sequence end-to-end:

1. Trigger. The user hits a transition point — finishes a level, taps “next,” submits a form. The publisher’s ad SDK (AdMob, AppLovin MAX, Unity LevelPlay, ironSource) or web ad server signals that an interstitial slot is open.
2. Bid request. The SDK sends an OpenRTB bid request including device, OS, geo, app or site category, user signals where consented, and the slot’s dimensions and format.
3. Auction. DSPs evaluate the impression and submit bids. In a header-bidding or unified-auction setup, SSPs and networks compete simultaneously rather than running through a waterfall.
4. Render. The winning creative — ideally pre-cached during the previous screen — renders full-screen.
5. Engagement window. Static creatives expose a close button immediately. Video typically locks the close button for up to five seconds; AdMob allows up to 12 seconds for high-engagement video and up to 30 seconds for some third-party bidding sources. Rewarded formats run 15–30 seconds and reward completion.
6. Outcome. Click-through, close, or completion. Impression, click, and post-click events fire back through the SDK to the DSP, the ad server, and the measurement vendor.

Step 4 is where most of the money goes missing. If the creative isn’t pre-cached and ready to render within roughly 500 milliseconds of the trigger, the user has already moved past the slot or the SDK times out. In our experience across thousands of rich-media campaigns, heavy creatives lose somewhere between 10% and 20% of paid impressions to this window alone.

Same creative file, same placement, different platforms — the version that loads faster gets shown more frequently because publisher ad servers reward better engagement. We ran one such test on Romania’s republica.ro with Turn Digital, our partner there, against Celtra’s platform using the same creative file. Our creatives delivered 3× the engagement and 2× the CTR, and the publisher’s ad server (AdOcean by Gemius) automatically routed more traffic to the better-performing version once the data came in.

The same dynamic applies on interstitial inventory, where pre-cache failure has the largest impact because the entire screen is at stake.

We’ll come back to pre-cache later — it’s the single largest source of avoidable underdelivery we see.

The five types of interstitial creative

The format is the canvas; the creative is what fills it. Five types are worth knowing, and they perform very differently. The choice between them should be driven by the campaign objective, not by what’s quickest to produce.

Static image interstitials

A single full-screen image with a call-to-action. Fast to produce, fast to load, easy to A/B test. They earn the lowest CPM of the interstitial family — but they’re the format we reach for when a campaign needs to scale across thousands of placements with consistent rendering. Branding bursts, retail promos, time-sensitive offers, app-install asks where the message can be communicated in one frame. Where they fail is when a brand tries to use them for storytelling that needs more than a single image to land.

Video interstitials

Short full-screen videos, typically 6–30 seconds, with a skippable close button after the 5-second forced view. Video is the dominant in-game ad format in mobile gaming and commands roughly a 40–60% eCPM premium over static interstitials. The conventional wisdom is that shorter is better; the data disagrees. Liftoff’s 2024 analysis found that long-form video ad spend grew 245% year-over-year, and that 31–60 second video frequently outperformed shorter cuts on conversion. The reason: when a video earns the user’s attention, longer narrative arcs justify the longer view. When it doesn’t, length is irrelevant — they close it.

Rich media interstitials

Full-screen interactive units combining images, video, animation, and interactive elements — swipes, taps, drags, hotspots, embedded mini-experiences. This is where storytelling lives in display advertising. Used well, rich media converts because the user does something inside the ad before clicking out, which is qualitatively different from passively watching a video.

The trade-off has historically been weight and build complexity. Many HTML5 workflows produce units that blow past the 200KB initial-load cap most exchanges enforce, particularly for highly interactive rich media. The creative ships anyway, but it gets quietly downranked and underdelivers.

NEXD Campaign Manager takes a different technical approach — using WebGL and GPU processing instead of HTML5 — which produces ads 5–10× lighter at the same creative complexity, with 5× faster load times and 3× better CTRs compared to HTML5 builds.

The Netflix Extraction 2 interstitial in the examples section below is a good illustration: a fully interactive playable mechanic, sniper-scope animation, video end-frame, all delivered inside the same 200KB initial-load window that most static interstitials struggle to clear. The production timeline compresses from weeks to days — agency teams using NEXD ship campaigns roughly 10× faster than the equivalent HTML5 workflow.

Playable interstitials

A try-before-install mini-experience embedded in the ad. The user plays for 15–60 seconds, then gets the install prompt. Playables are mostly used for gaming user acquisition, but we’ve seen them work for non-gaming app installs and product demos too. Liftoff’s 2024 Mobile Ad Creative Index reports that playable ads drive 20× more installs than banners in gaming. Their 2026 update has playable IPM (installs per mille) at 4.8 on average — outperforming video (2.9) by 66% and static (1.4) by 243%. They’re also the most expensive creative type to produce, which is why playable demand reliably outstrips supply.

Rewarded interstitials

A variant where the user opts in to watch — typically a 15–30 second video — in exchange for an in-app reward. Because participation is voluntary, completion rates run higher than non-rewarded video (Adjust’s data puts the average at 75.8%; some inventory exceeds 90%) and they earn the highest eCPMs of any in-app format: $15–$30 in tier-1 markets. Rewarded sits adjacent to standard interstitials in the bid stream, and most performance advertisers buy both with different bid strategies.

Interstitial ad examples (and the creative mechanics behind them)

The most useful way to look at interstitial ad examples isn’t by brand or by vertical — it’s by creative mechanic. The mechanic is the transferable idea: the bit you can lift and pitch to your own client next week, regardless of category. Here are five interstitial ads we’ve shipped, each built around a mechanic that worked. All five are embedded live — tap, drag, and swipe directly inside the ads to see how they behave.

1. The “find it” mechanic — Netflix, Extraction 2

A playable interstitial built to promote the Netflix film. The user looks through a sniper scope, scans the screen, and takes out the villains hidden in the scene. The mechanic borrows from first-person gaming and turns the ad into a 15-second mini-mission. Once the user completes it, the end card invites them to watch the film on Netflix.

Why it works: the user is doing something narratively connected to the product (the film is about an extraction mission), not just tapping a generic playable shell. The mechanic also produces a natural “completion” moment that justifies the CTA.

Transferable to: any campaign with a narrative product (films, games, books, TV series, true-crime podcasts), spy/security categories, search-driven verticals (real estate “find your home,” travel “spot the destination”).

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2. The “playable mini-game” mechanic — Disney+ / Encanto

A custom gamified interstitial built for the Disney+ release of Encanto. The user controls Luisa — Encanto’s super-strong sister — moving her left and right across the bottom of the screen to catch the donkeys falling from above. A short, self-paced mini-game starring two of the film’s recognizable characters. When the user wins, the ad transitions to a CTA to watch on Disney+.

Why it works: the character does the heavy lifting. The user isn’t being asked to engage with a brand — they’re being asked to play with something they already recognize and like. The mini-game is short enough to not feel like a commitment and the reward (winning) is intrinsic, not extrinsic.

Transferable to: any brand with a mascot, character, or recognizable IP — put the character front and center as the playable element. Works for entertainment IP, cereal/snack mascots, sports team mascots, insurance brand characters, telco/banking mascots, anything where the audience already has affinity with a recognizable figure. The format converts that latent recognition into 10–20 seconds of active engagement.

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3. The “score-to-win” mechanic — Visa / FIFA World Cup Qatar

A gamified interstitial built for Visa’s FIFA World Cup Qatar sponsorship. The user is invited to play a quick football game and score three goals — short enough to finish in under 30 seconds. On completion, the ad reveals the offer: pay with Visa and stand a chance to win a trip to the FIFA World Cup 2022.

Why it works: the mechanic mirrors the campaign’s emotional payoff. The user doesn’t just see a World Cup ad — they do a tiny version of what the prize represents. The earned “you scored three goals” moment makes the CTA feel like a reward for performance, not an interruption.

Transferable to: any brand whose audience enjoys sports — sponsorships tied to football, basketball, tennis, golf, motorsport, esports. Works equally for sports-adjacent verticals: betting platforms, sports apparel, energy drinks, fan-loyalty programs, broadcast subscription services. The pattern is identical regardless of sport — pick the dominant skill action (kick, shoot, swing, drive), make a 15-30 second mini-version of it, tie the reveal to a campaign-relevant prize.

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4. The “swipe to swap” mechanic — Sadolin

A custom interstitial format for Sadolin paints. One scene — a room, a wall, a piece of furniture — sits as the background. The user swipes left and right to swap the color of the surface in real time. Same room, different paint shade, every swipe. The product becomes immediately, visually personal.

Why it works: color choice is a high-friction decision the user usually has to imagine. The swipe makes the decision tangible inside the ad itself, which is what gets the user committed enough to click through.

Transferable to: paint, cosmetics (lip color, hair color, foundation), automotive (color and trim), interiors and furniture, fashion (color variants of the same item), tile and flooring.

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5. The “chatbot” mechanic — Swedbank

An interstitial styled as a chat between two friends. The user watches a scripted conversation play out, message by message, where one person comes up with increasingly absurd reasons to delay paying back a small amount of money. The humor lands because everyone recognizes the awkwardness of asking a friend for money — and the punchline is that Swedbank’s app makes the transfer instant, so there are no excuses left.

Why it works: the chat format mimics a medium the audience already spends hours in every day, so the ad doesn’t feel like advertising. The humor earns the user’s attention voluntarily — they keep tapping to see the next message because they want to know the punchline, not because they were forced to wait through a video. The product message lands at the end, after the joke has already made it feel native.

Transferable to: any product where the value is fastest understood through a small, relatable everyday scenario — banking and payments, insurance (“the moment you wish you’d had a policy”), telco (“the dropped call moment”), food delivery, ride-hailing, dating apps, consumer SaaS. The pattern is: identify the tiny social friction your product removes, dramatize it as a short scripted exchange, let the punchline carry the brand message.

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What ties these together is the principle that interstitial ads earn their premium when the user does something inside the ad rather than just watching it. A static interstitial that uses the full screen for a still image is leaving the format’s biggest advantage unused. The mechanic is what makes the full screen worth it.

Browse 50+ live interstitial examples in the NEXD Ad Gallery →

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Interstitial ad sizes and specifications

Two ways to think about interstitial sizes, and the answer depends on how your creative is built.

Interstitial ad sizes: the legacy per-size approach

The IAB standardized a handful of interstitial sizes years ago, and a lot of creative still gets produced this way — separate files for smartphone portrait, smartphone landscape, tablet portrait, tablet landscape. Your trafficking team uploads each one, and the SDK picks the closest match at serve time. These are the IAB-recognized and Google Ad Manager-supported sizes:

Device class	Portrait	Landscape
Smartphone	320×480	480×320
Modern smartphone / phablet	320×568, 375×667	568×320, 667×375
Tablet	768×1024	1024×768
Desktop	Responsive to viewport	Responsive to viewport

The problem with the per-size approach is the long tail. More than 55% of the global mobile market is now on high-aspect-ratio screens — notched iPhones, tall Android flagships, foldables — and the gap between phone-portrait and tablet-portrait keeps widening. A 320×480 creative on a tall modern device fills only ~70% of the screen, with empty bars top and bottom. Designing for every aspect ratio individually means more files, more QA, more places things break.

The modern approach: responsive interstitial tag

A single tag that adapts to the device’s actual screen and fills the viewport in portrait without per-size files. This is how NEXD ships interstitial creative — one tag, every device, screen-filling in portrait regardless of aspect ratio.

The creative is designed against two layers: a background that covers full height (up to 640×1280 px) so there are no black or white bars on any device, and a safe area in the center (max 854 px height) where the essential content sits. CTA buttons, logos, and other overlay assets are positioned by NEXD’s layout system rather than being baked into the file, so they appear correctly on screens of any aspect ratio. The same creative fills a 320×480 budget phone, a 6.7″ notched flagship, and a foldable in folded mode without separate builds.

What to verify on every interstitial creative before launch

• Initial load weight: under 200 KB. This is the single most important spec for delivered performance. Most rich-media campaigns that quietly underdeliver fail here. Reject anything heavier before it goes live.
• Polite load (post-impression): under 500 KB for HTML5 / rich media; 2–5 MB for video depending on network. Your creative partner should report this number alongside the build.
• Responsive vs per-size delivery: ask your creative partner which approach they use. Per-size workflows produce more files to QA and more places for the layout to break on long-tail devices. A responsive tag avoids that entirely.
• Safe-area handling: if using a responsive approach, confirm essential content sits inside the safe area and that overlay assets (CTA, logo) are positioned by the system, not baked into the background.
• Close button safe zone: top-left and top-right corners (typically 50×50 px on mobile) are reserved by MRAID for the system close button. Nothing should sit there.
• Verification compatibility: IAS or DoubleVerify tags at the placement level for measurement and brand safety. Confirm before scaling spend.
• MRAID 3.0 compliance: ask your creative partner to confirm. This is the rich-media standard every major mobile exchange expects. Builds without it get rejected by some inventory.

Check sizes for any DSP or publisher with the NEXD Specs Calculator →

What performance to expect from interstitial ads

Most “interstitial benchmarks” articles online are either too vague to be useful or sourced from a single ad network’s slice of inventory. Here’s what’s reasonable to expect, with sources:

Interstitial ad CTR benchmarks

• Mobile banner: 0.10–0.30%
• Interstitial on mobile web: 0.5–1.5%
• Interstitial in-app, Android: 4–5% (PropellerAds’ published CTR data)
• Smaato + Liftoff joint study (3 trillion ad requests, 80 billion impressions): interstitials produce 18× higher CTR than banners and 4.6× higher eCPM
• iOS games CTR: 4.27% (Business of Apps 2026)

What we see in our own data tracks these benchmarks: interactive interstitial creative regularly delivers CTRs in the 3–7% range on premium inventory, with viewability typically above 90% (the format guarantees most of it). The Netflix and Disney+ playable interstitials in the examples section both ran on premium streaming inventory and over-delivered against the static-interstitial baselines they were compared to.

Interstitial eCPM benchmarks (tier-1 markets, Q4 2024–Q1 2026)

Format	iOS (tier-1)	Android (tier-1)	Global average
Banner	$0.50–$1.50	$0.50–$1.50	$0.20–$0.80
Static interstitial	$4–$8	$3–$7	$2.50–$5
Video interstitial	$6–$14	$5–$11	$3–$7
Playable interstitial	$15–$25	$12–$20	$6–$12
Rewarded video	$15–$30	$12–$25	$8–$18

Interstitial conversion benchmarks

Statista’s analysis (via Business of Apps) puts interstitial in-app conversion at over 20% on Android and close to 15% on iOS — the highest of any in-app format. App install campaigns benefit disproportionately because the format gives the brand a full screen to demonstrate value before the install prompt.

The shift to attention metrics

This is where most coverage of interstitial benchmarks is outdated. In November 2025, the IAB and MRC released the first standardized Attention Measurement Guidelines after two years of work by a 200+ expert task force. The shift is real and ongoing: 47% of buy-side decision-makers told the IAB they expected to focus more on attention metrics, and the leading verification vendors (DoubleVerify, IAS, Adelaide, Lumen, Realeyes) have all released attention products in the last 18 months.

The relevant attention metrics for interstitial campaigns are time-in-view, interaction patterns (clicks, hovers, drags, swipes), and completion rate. These matter more for brand campaigns than for performance campaigns, but they’re rapidly becoming the standard KPI set for both.

Interstitial ads have an inherent advantage in measurement: the format guarantees 100% viewable surface area, and any in-unit interactivity — swipes, taps on different elements, time spent on each screen, video completion within the unit — is captured directly by the creative. A static banner gives you a click. A rich-media interstitial gives you the full interaction shape — which assets got attention, in what order, for how long. NEXD’s analytics integrate with the standard programmatic verification stack (IAS, DoubleVerify) at the placement level, with the in-unit engagement data reported alongside.

Across our own client data, lighter WebGL-rendered interstitials consistently deliver longer dwell times and higher engagement rates than HTML5 equivalents — and because the underlying creative is lighter, the same impression can carry more. A real mini-game, 3D product models, multi-step interactivity. HTML5 hits its weight ceiling well before this kind of creative is possible.

Why most interstitial ads underperform their predicted CPM (and how to fix it)

Here’s the thing nobody talks about. The CPM you bid is the CPM you bid; the CPM you deliver is something else entirely. The gap between the two is where campaigns quietly bleed out.

Three causes of underdelivery account for most of it, in our experience:

1. The creative misses spec

The 200KB initial-load cap is non-negotiable on most exchanges. Traditional HTML5 rich-media tools routinely produce builds well over that cap. The creative still ships, but the exchange downranks it, the publisher’s ad server routes less traffic to it, and your effective CPM drops without anyone noticing exactly why. We see this most clearly when running side-by-side tests: same creative concept, same placement, the lighter version wins delivery on volume even when the heavier version has a higher static CTR in isolated tests.

2. The creative misses the pre-cache window

If the ad doesn’t render within ~500ms of the trigger, the user has already moved past or the SDK times out. Pre-cache works by loading the next ad in the background during the previous screen — but it only works if the ad is small enough to cache quickly. Heavy creatives miss the window. In side-by-side comparisons we run for clients, the lighter WebGL version of the same creative concept consistently wins on delivered CTR — not because the creative is better designed, but because it actually renders in time, every time, on every device.

3. The creative isn’t optimized for the placement type

Static creative on a video-friendly placement, or a heavy interactive unit on inventory that only supports VAST tags — both result in fallback rendering or rejected impressions. This is usually a trafficking problem rather than a creative problem, but it shows up as underdelivery in the reporting.

The rendering technology question interstitial buyers don’t ask

Most discussions of interstitial performance skip over the technology rendering the ad. That’s a mistake, because rendering determines whether the creative hits spec, hits the cache window, and hits its predicted CPM. HTML5 — the default for almost every creative management platform — is CPU-bound and produces heavier builds. WebGL uses the device’s GPU and produces ads at a fraction of the file weight for the same creative complexity. This is the same shift browser games went through years ago: at any meaningful level of interactive complexity, GPU rendering wins on speed and weight.

That’s the architectural decision NEXD is built on. We don’t use HTML5 for the rendering — which is why our ads come in at a fraction of HTML5 weight for the same creative complexity. Across the millions of interstitial impressions we’ve served, that has translated into over 10.3 million kg of CO₂ saved in cumulative ad delivery (more on that further down).

What this means for you as a buyer: when evaluating creative production partners, ask which rendering technology they use. If the answer is “standard HTML5,” you’re choosing a platform that hits the 200KB cap easily and misses the pre-cache window more often. Lighter rendering is now a procurement question, not just a creative one.

Scaling variations: DCO for interstitial campaigns

Creative fatigue is happening faster than most coverage acknowledges. Liftoff’s 2026 data shows fatigue onset for video ads on Meta dropping from 14 days in 2024 to 9.2 days in 2026, and AppsFlyer’s 2026 report found 78% of top-quartile campaigns now refresh creative at least weekly, up from 41% in 2024.

What that means for interstitial campaigns specifically: you need variations. Not “one creative across all geos” — many variations. Frequency capping means the same user sees the same ad too often unless you have alternatives. Geo-targeting needs different creative per market. Languages, audiences, sales periods, dayparting — each multiplies the variation count. A campaign across 10 markets in 3 languages with weekly refreshes for two months is 240+ creative variations.

Hand-building each variation in HTML5 doesn’t scale. That’s where dynamic creative optimization (DCO) earns its keep. NEXD’s approach: one tag → many creatives → infinite variations, driven by two scheduling layers:

• Rule-based scheduling (we call this “Flights”). You define when, where, and to whom each variant delivers, using IF / AND / OR / ELSE logic across location, language, time, dayparting, and audience signals. One tag serves all variations; the platform decides which to show.
• Performance-based prioritization (“Self-Optimizing Flights”). Variants run randomly until enough data is collected, then the system optimizes toward CTR or engagement rate, re-optimizing every six hours. The winning creatives get more traffic automatically; underperformers get suppressed.

The production side is what makes this work at the cadence the market now requires. NEXD ships campaigns roughly 10× faster than traditional HTML5 workflows — not by cutting creative quality, but by removing the rebuild step every time a variation is needed.

Interstitial ad best practices that actually move performance

Three practices that separate interstitial campaigns delivering predicted CPMs from the ones quietly underdelivering. Each one is something a media buyer, ad-ops lead, or agency creative team can act on directly:

Cap frequency at both the DSP and the ad server

Industry consensus is one in-app interstitial every three to five minutes of session time, with a hard cap of one per user-initiated transition. For media buying, that translates to 2–3 impressions per user per day on performance campaigns, 1–2 on premium brand campaigns. Capping in only one place leaks frequency in cross-network buys.

Brief creative under 200 KB initial load

The single biggest hidden cost in interstitial campaigns isn’t the media — it’s heavy creative that misses the 500ms pre-cache window and never renders. Programmatic exchanges cap initial-load weight at 200 KB. Anything heavier than that fails to render for a meaningful share of impressions you paid for, and the publisher’s ad server quietly downranks your buy from there.

You don’t pre-cache the creative — your SSP or DSP does. But you control what gets built and shipped. Lightweight creative is the prerequisite for everything else to work.

Test creative, then placement, then frequency — in that order

Creative quality drives the biggest swings. Placement is the next-largest lever. Frequency cap tuning is where you optimize the long tail. We see teams reverse this order and lose months on placement testing that the creative quality was always going to overwhelm. WARC’s research (drawing on Paul Dyson’s analysis of profitability multipliers, presented at Thinkbox) confirms creative quality is now the single most important actionable lever for marketers, with a 12× profitability multiplier — up from 10× in 2014.

Interstitial ads vs. pop-ups vs. banner ads

The three terms get used interchangeably and shouldn’t be. The distinctions matter for both campaign planning and (as we’ll see in a minute) for SEO compliance on your own website.

	Banner ad	Pop-up ad	Interstitial ad
Coverage	Small fixed strip	Partial overlay	Full screen
When it appears	Persistent on screen	Triggered mid-task	At transition points
User control	Easy to ignore	Must close to continue	Tap through or close
Typical CTR	0.10–0.30%	Variable, mis-click inflated	0.5–1.5% web; 4–5% in-app
CPM (tier-1)	$0.50–$2.80	Low to mid	$4–$12 (up to $25 for playable)
Google SEO penalty risk	None at reasonable size	High on mobile web	High only on landing from search
Best for	Always-on brand presence	Email capture (carefully)	App installs, brand campaigns, storytelling

The pop-up vs interstitial line is partly cultural — plenty of people use the words interchangeably — but in advertising the distinction is technical. A pop-up covers part of the screen during a task. An interstitial covers the full screen at a transition.

One source of confusion worth flagging: Google has a separate SEO concept called “intrusive interstitials” that applies to overlays on websites (not to in-app ads). It penalizes content sites that block search visitors with full-screen overlays. If you run a content site and worry about this, search “Google intrusive interstitials policy” for the dedicated SEO coverage — it’s a separate topic from the ad format this article covers.

A note on sustainability

This used to be a niche topic in adtech conversations. It isn’t anymore, especially in EMEA, where it’s increasingly turning up as a brief requirement from procurement.

The digital advertising industry emits roughly 7.2 million metric tons of CO₂ annually — equivalent to the electricity usage of 1.4 million US households (Scope3, 2023). Programmatic advertising alone produces 215,000 metric tonnes per month across the US, UK, Germany, France, and Australia. The global average works out to 333 grams of CO₂ per 1,000 impressions. Ebiquity and Scope3’s joint 2022 research found that 15% of brand ad spend is wasted on high-carbon, no-ROI placements — a figure that combines sustainability concerns with simple budget efficiency.

Creative weight is one of the biggest levers an advertiser controls directly. Every megabyte of unnecessary creative weight, multiplied across millions of impressions, is energy spent on data centers, network transmission, and end-user device processing. Lighter creative is lower carbon, full stop.

NEXD has been measuring this since the start — we’ve always built on WebGL, not migrated to it. We’re certified by the Green Web Foundation, our carbon data is powered by Scope3 (the industry standard, and the same data source used by Adform, Adelaide, and the ANA’s 2024 marketing emissions report), and across the campaigns we’ve served we’ve cumulatively saved over 10.3 million kg of CO₂ versus equivalent HTML5 delivery.

One recent campaign — End Food Waste Australia — cut data transmission by 89% and avoided 956 kg of CO₂ while achieving 55–61% engagement and 15-second average dwell time. Our sustainability page tracks the running total in real time.

Building interstitial campaigns with NEXD

Interstitial ads are the highest-CPM non-rewarded format in mobile, the highest-conversion display format for app installs, and the place where creative quality has the largest single impact on delivered performance — provided the creative is built to deliver against that potential: fast enough to pre-cache, light enough to clear exchange specs, varied enough to avoid fatigue, measured against the metrics that matter.

That’s what NEXD Campaign Manager is built for:

• WebGL rendering instead of HTML5 — lighter, faster, higher CTR
• Production tooling that ships campaigns 10× faster than HTML5 workflows
• DCO for rule-based and self-optimizing creative delivery from one tag
• Built-in engagement and attention tracking aligned with the IAB/MRC November 2025 standards
• Scope3-powered carbon measurement on every impression served

We’ve built interstitial ad campaigns for brands including Netflix, Disney+, A1, Swedbank, and Sadolin — typically through their agencies. If the interstitial campaigns you’re shipping today are still being built in HTML5, the free trial gives you everything to test what a WebGL-rendered interstitial delivers against your current baseline.

WebGL rendering isn’t always the right answer. For simple single-frame static interstitials — a retail promo, a flash-sale announcement, a basic app-install ask where the message lands in one image — HTML5 is fine and the rendering choice doesn’t move performance. Where WebGL matters is when the creative carries any meaningful interactivity, video integration, or animation: the kind of unit that historically blows past the 200 KB cap. If your campaign is single-frame static across the board, you don’t need us. If it’s anything more, the rendering layer becomes the difference between predicted CPM and delivered CPM.

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Frequently asked questions

What are interstitial ads?

Interstitial ads are full-screen ads that appear at natural transition points in apps and websites — between game levels, after a form submits, or when moving between content pages. The user must tap through or close the ad before continuing. Liftoff’s 2024 data has them converting to install 30× more often than banner ads in gaming.

What are the standard interstitial ad sizes?

Standard interstitial ad sizes are 320×480 and 480×320 for smartphones, and 768×1024 and 1024×768 for tablets. Desktop is responsive to viewport. Initial-load file weight is capped at 200 KB on most programmatic exchanges, with creatives required to fill at least 50% of screen width and 40% of screen height.

What is the difference between interstitial ads and pop-up ads?

Pop-ups cover part of the screen during a user’s task; interstitial ads cover the entire screen at a transition point between tasks. Pop-ups are more likely to violate Google’s mobile interstitial policy because they tend to appear immediately after a search-result click.

How much do interstitial ads pay?

Interstitial ad eCPMs in tier-1 markets typically run $4–$8 for static, $6–$14 for video, $15–$25 for playable, and $15–$30 for rewarded video. Global averages are roughly half of tier-1 rates. The US leads on iOS interstitial CPMs at around $14 in Q4 2024. These are the rates an advertiser pays per thousand impressions; the publisher receives a share after the SSP and ad server take their fees.

Does Google penalize interstitial ads?

Google penalizes “intrusive interstitials” — overlays that block content immediately when users arrive from mobile search. The penalty does not apply to in-app interstitial ads, exit-intent pop-ups, cookie consent notices, age verification, or login dialogs on private content. The 2024 Content Warehouse leak confirmed it operates via the violatesMobileInterstitialPolicy attribute.

What’s the difference between interstitial ads and rewarded ads?

Rewarded ads are interstitials the user opts in to watch in exchange for an in-app reward, usually a 15–30 second video. Standard interstitials interrupt without consent; rewarded require it. Completion rates run higher (Adjust reports 75.8% average) and eCPMs run roughly 2–3× higher than non-rewarded video.

When do interstitial ads work best?

Interstitial ads work best at task-completion transitions — game-level completion, form submission, article finish, video end. They fail when placed mid-task, on app launch, immediately after another ad, or on a page where the user just landed from search. Best practice is one in-app interstitial every 3–5 minutes of session time.