Interstitial ads CPM is usually much higher than banner CPM because the ad fills the whole screen, is almost always seen, and can carry video. But there's no single rate. It changes with country, device, niche, season and how often you show the ad, so judge interstitials by page RPM, not CPM.
Here's the catch. A full-screen ad that pays several times more per impression can still cost you money if readers leave sooner or view fewer pages. And Google has firm rules on where interstitial ads may appear, on the web and in apps. This guide shows which CPM figures are actually sourced, which rules apply to you, and how to test interstitials safely. If you'd like a second pair of eyes on the numbers, our reporting and yield service does exactly this kind of test.
Why interstitial ads CPM is higher than banner CPM
Interstitial ads earn a higher CPM because buyers get the whole screen and a near-certain view. An interstitial is a full-page ad shown between two pieces of content, such as between pages on a site or between levels in a game. Google's Ad Manager help calls web interstitials "full-page web ads" and an "additional inventory and revenue source".
A few things push the price up:
- Viewability. The ad covers the screen until the user closes it, so it's hard to miss. Buyers who pay for viewable impressions value that.
- Size and formats. A full screen fits large display, rich media and video creatives, and more formats means more buyers bidding.
- Scarcity. Frequency caps limit how many interstitials each user sees, so there are far fewer of these impressions than banner impressions.
- Attention. There's nothing else on screen competing with the ad.
So when people compare interstitial vs banner CPM (see our guide to banner ad sizes for the banner side), the gap is real. What it isn't is a fixed multiple you can count on.
How much do interstitial ads pay? What the sourced data shows
Interstitial ads pay more per impression than banners in every source we found, but very few sources say where their numbers come from. Many rate tables online have no date, no sample and no source. We only quote figures with a named source below, and we'd treat them as direction, not a forecast for your site.
| Source | What it says | Date and context |
|---|---|---|
| Google AdMob case study | Language-app maker Bravolol saw CPM rise tenfold within a year of adding interstitial ads to its apps | Interstitials added in 2013; one developer's apps, with AdMob Mediation. No placement or frequency details given |
| AdMonsters report on a publisher study | Average interstitial eCPM was 4,094% higher than average banner eCPM; 5,173% on desktop and 3,241% on mobile | Published January 2023; a study run by a monetization company on its own publishers. Sample and period aren't stated in the article |
Notice what's missing. Neither source says what your page RPM or total revenue did. A bigger CPM on a small number of impressions is a different thing from more money per visit. That's the gap the next section covers.
What moves interstitial ads CPM up or down
Interstitial ads CPM moves with the same forces as any display price, plus a few that only apply to full-screen ads. These are the ones we check first when a publisher's full-screen numbers look odd:
- Visitor country. Advertisers pay more in the markets where they sell more, so the same interstitial earns very different amounts in different countries.
- Platform and device. iOS and Android, phones and tablets, mobile web and desktop all sell at different prices. Split your report by each before you compare anything.
- Niche. Topics that attract bigger budgets, like finance or software, lift full-screen prices the same way they lift banners.
- Creative types allowed. A slot that accepts video and rich media as well as static images has more buyers bidding for it.
- Timing. An interstitial at a natural break, like a finished level or a link click, is less likely to cause the accidental clicks AdMob warns about.
- Number of buyers. More demand sources bidding on each impression raises the clearing price.
Frequency sits apart from these. A looser cap adds impressions, but it's also the setting most likely to shorten sessions, so treat it as a test, not a revenue dial.
Where interstitial ad demand comes from
Interstitial demand reaches you through your ad platform, so how many buyers compete depends on your setup, not only the format. On the web, Google's full-screen ads come through Ad Manager web interstitials or AdSense vignettes. In apps, AdMob serves them and can add third-party networks through mediation.
In apps, the biggest lever is bidding. AdMob lets ad sources compete in a real-time auction for each request instead of waiting in a fixed waterfall order, which gives every buyer a fair shot at your best impressions. On the web, header bidding adds outside buyers next to Google's demand, and our header bidding service covers how that's set up.
Whatever you add, judge it the same way. A new source that lifts the format's CPM but slows the page or the app can still cost you money overall.
Why a higher CPM can still lower your page RPM
A high interstitial CPM doesn't guarantee more revenue, because it's earned on few impressions and can cost you page views. Page RPM is what decides it. Google's RPM help page gives the formula: estimated earnings divided by page views, times 1,000.
Think about what an interstitial changes. It adds one expensive impression every so often. But if it annoys readers, some leave instead of clicking to the next article. Each lost page view also loses every banner, in-content and anchor impression that page would have shown. You can't see that loss in the interstitial's own report.
So the numbers to watch are page RPM, pages per session and session length, for the whole site, before and after. If you want a refresher on how CPM and RPM differ, our guide to AdSense CPM vs RPM walks through it. To see what page RPM means in real money, our breakdown of what 1 million impressions per month earns runs the sums.
Interstitial ad rules from Google and the Coalition for Better Ads
Interstitial ad rules come from four places: Google Search, the Better Ads Standards, Google's ad platforms on the web, and AdMob in apps. Break them and you risk poor search performance, a filtered ad experience or a policy strike.
Google Search: avoid intrusive interstitials
Google's guidance on intrusive interstitials says not to obscure the entire page with interstitials, and warns that intrusive dialogs "may lead to poor search performance". Legally required ones, like age gates, are the exception. Google's own web interstitials fire on triggers like a link click, not the moment a visitor lands.
Better Ads Standards
The Coalition for Better Ads standards list ad experiences that fall below what people accept. On mobile that includes prestitial ads, which appear before content loads, postitial ads with a countdown, and full-screen scrollover ads. On desktop it includes prestitial ads with a countdown. A full-page ad that blocks the content a visitor came for is the pattern to avoid.
Ad Manager web interstitials and AdSense vignette ads
Google's web interstitials are built to respect the Better Ads Standards. In Ad Manager, the web interstitials help page lists the triggers: clicking a link, returning to a hidden tab, scrolling back up at the end of an article, and a few opt-in ones. The default cap is 1 impression per 10 minutes, and you can lower it to 1 per minute. Users can close the ad with the browser's back button.
Web interstitials need their own cap, because Ad Manager's format frequency caps page says the "Any" format doesn't apply to them. They also need local storage, so sites using IAB TCF v2.2 need consent for Purpose 1.
In AdSense, the same idea is called vignette ads. Google's vignette frequency page says they show when a user leaves a page or comes back to it. The default gap is 10 minutes, adjustable from 1 minute to 1 hour under Ads, then Overlay formats, then Advanced settings. Google also added additional vignette triggers in 2026, such as the back button and returning after 30 seconds of inactivity. They respect your frequency cap, and you can opt out in the same menu.
AdMob interstitial rules for apps
AdMob's disallowed interstitial implementations are specific:
- No interstitials on app load or when the user exits the app.
- No more than one interstitial after every two user actions, Back button included.
- No interstitial straight after the user closes another one.
- Nothing that stops people viewing the app's core content.
- No surprise ads during gameplay or typing. Show them at logical breaks, and preload so a slow load doesn't pop one up after the next screen opens.
AdMob's interstitial ad guidance adds that they're "best placed at natural app transition points", such as finishing a level.
Close button delays and rewarded interstitials
App interstitials don't always close straight away. The same AdMob page says some interstitials can take up to 5 seconds to show a close option, video interstitials up to 12 seconds when high-engagement ads are on, and video from third-party bidding sources up to 30 seconds. Factor that wait into where you place them.
AdMob also has a rewarded interstitial format, still in beta. Its rewarded interstitial overview says these ads appear automatically at natural app transitions, need an intro screen that announces the reward and lets users opt out, and serve only skippable ads.
Web interstitial ads vs AdMob interstitial ads
Web interstitial ads and app interstitials share a format but not a setup. On the web, Google decides the moment within your triggers and cap. In an app, you choose the moment in code, within AdMob's rules.
| Web (Ad Manager, AdSense vignettes) | App (AdMob, Google Mobile Ads SDK) | |
|---|---|---|
| When it shows | On Google's triggers, such as a link click or a return to the tab | Where your code calls it, at a natural break |
| Frequency | Time-based cap, 10 minutes by default | Your own logic, within the "one per two actions" rule |
| Main risk | Fewer page views per session, search guidance on intrusive interstitials | Policy strikes for surprise or back-to-back ads, users quitting the app |
| Metric to judge | Page RPM and pages per session | Revenue per daily active user and retention |
If you run apps, our app monetization service covers placement and mediation, and it's worth checking your app-ads.txt setup before you add new demand.
How to test interstitial ads without losing revenue
Test interstitial ads like any layout change: one change, a conservative cap, a clean comparison and a decision on total revenue. This is the order we follow when a publisher asks us about full-screen ads.
- Write down your baseline. Note page RPM, pages per session and session length for the last few weeks, split by device and top countries.
- Start with Google's default cap. One per 10 minutes is a sensible first setting. Don't start at 1 minute.
- Change one thing. Don't add interstitials the same week you move other units or change partners.
- Split the test if you can. Run it on one section or one device first, and keep a similar section as the control.
- Run it long enough. Two weeks covers both weekdays and weekends. Avoid comparing across month ends or big seasonal shifts.
- Decide on the whole site's numbers. Keep interstitials if page RPM rose and pages per session held. Then try a shorter cap as a second test.
Watch for invalid traffic as well. Accidental clicks on full-screen ads can trigger policy issues, and our compliance and IVT service can help if that happens.
Frequently asked questions about interstitial ads CPM
Why do interstitial ads have higher CPMs?
They fill the whole screen, are very likely to be seen, can carry video and rich media, and are shown less often than banners because of frequency caps. Buyers pay more for that attention.
Are interstitial ads against Google's rules?
No. Google sells them itself through Ad Manager, AdSense vignettes and AdMob. What's against the rules is how some are placed: covering content a visitor just arrived for, ads on app launch or exit, back-to-back ads, or surprise ads mid-task.
How often should interstitial ads show?
Google's default for web interstitials and vignettes is one per user every 10 minutes. In apps, AdMob allows no more than one after every two user actions. Start at the default and only show them more often if page RPM and sessions hold up.
Do vignette ads hurt SEO?
Google's search guidance warns against interstitials that cover the whole page and make content hard to reach. Vignettes show when someone leaves or returns to a page rather than on arrival, but you should still watch your search traffic during a test.
What ad formats can an interstitial show?
A full screen fits static display, rich media and video creatives. In apps, AdMob also offers rewarded interstitials, which give users a reward for watching and must be skippable.
Are interstitial ads effective?
For advertisers, yes. A full-screen ad is hard to miss, which is why buyers pay more for it. For you, they're effective only when page RPM or revenue per user rises and sessions hold, which is exactly what the test above measures.
Is a good interstitial CPM the same as good revenue?
No. Revenue depends on page RPM, which counts every ad on every page view. A high interstitial CPM can be cancelled out if visitors view fewer pages.
Next step: test interstitials on page RPM
Interstitial ads CPM will look strong in almost any report. Whether full-screen ads pay depends on what they do to page RPM and sessions, inside Google's rules. Set a baseline, start at the 10-minute cap, and judge the whole site. If you'd like us to set up the test or read the results with you, see our reporting and yield service or contact MH AdX.
