What Are Interstitial Ads? Best Practices, Sizes and Google Play Rules

An interstitial ad is a full-screen ad that appears at a break in an app or website, covering the content until the person closes it or taps it. The word means something placed between things. Because it takes over the whole screen, it pays far better than a small banner, and because it interrupts, it can also drive people away when it is used badly.

For developers, the question is how to earn from interstitials without damaging retention or breaking store rules. For advertisers, it is how to make use of a few seconds of full attention. This guide covers both.

Formats and sizes

Interstitials usually come in three formats:

• Static. A full-screen image with a close button. Lightweight and cheap to make, though the least engaging.
• Video. Usually skippable after a few seconds, and often followed by an end card. The most common format in mobile games.
• Interactive or playable. The viewer can try something in the ad itself. A playable ad is usually served in interstitial or rewarded slots.

The long-standing display sizes are 320 x 480 portrait and 480 x 320 landscape for phones, with 768 x 1024 and 1024 x 768 for tablets. In practice, modern creatives should be responsive and fill screens of many shapes. A static image should be supplied at a higher resolution than those legacy sizes, and interactive ads need to adapt to the device. Portrait and landscape playable ads deals with the layout work.

The rules that matter

Interstitials have the strictest guidelines of any common format. Breaking them can bring an app enforcement action, or limit its ad serving. The two lists below are from Google's documentation in October 2026. On iOS, Apple's App Review Guidelines also require interstitials to be clearly marked as ads, not to trick people into tapping, and to offer easy, visible close or skip buttons. Always read the current wording.

Google Play Ads policy

• Full-screen interstitials of any format that show unexpectedly are not allowed, for example when a person has chosen to do something else.
• Ads that appear during gameplay at the beginning of a level, or at the beginning of a content segment, are not allowed.
• Full-screen video interstitials that appear before the app's loading (splash) screen are not allowed.
• Full-screen interstitials of any format that cannot be closed after 15 seconds are not allowed. Opt-in ads, or ones that do not interrupt, such as those after a score screen, may run longer.
• Ads must be easy to dismiss without penalty, and may not use a false dismiss button to force clicks.

Rewarded ads the user explicitly opts into are excluded from the rule about the beginning of a level.

AdMob implementation guidance

AdMob adds its own limits for publishers:

• Show interstitials only at logical breaks, such as between levels or pages, and pre-load them so they do not appear suddenly after new content has loaded.
• Do not place them on app load or on app exit. Google points to the app open format for launch and return moments.
• Do not show an ad after every user action. The stated limit is no more than one interstitial after every two user actions, including presses of the Back button.
• Do not show an interstitial immediately after a user closes another one.
• Do not show ads when the app is in the background, or launch them unexpectedly during play, form entry or reading.

Where to place them

A good placement is a moment the player already understands as a pause.

• After a level ends and its result has been shown. This is the classic spot. Let the player see the score first, because an ad that hides the win takes away the pleasure.
• After a run or a match, on the way back to the menu.
• Between sections of content, such as finishing an article, a chapter or a set of results.
• When leaving a task the user has finished, such as saving a file or completing a transaction.

Avoid moments of intent, such as when the player taps Next and wants to play. The same screen can be fine or terrible, depending on whether the ad interrupts something the person just asked for. Google Play's guidance draws this line too: a person tapping a button to start something should get that something.

Apps with no levels, such as idle games or some puzzles, have fewer natural breaks. Google's guidance says placement there needs good judgement so the ad does not get in the way of the app. Time-based caps are usually better than action-based triggers for these.

How often to show them

There is no universally right number. The right frequency is the point where extra ad revenue stops making up for the players you lose. Here is a practical way to find it:

1. Give new players a grace period. Avoid interstitials in the first session, or the first few levels, so people can decide they like your game first.
2. Set a cooldown, in time, between ads as well as a cap per session or day. Time-based caps stop a fast player from seeing an ad after every quick level.
3. Test frequencies against each other with random new-user groups. Common tests compare ads after every two, three or four levels, or set 30, 60 or 90 second minimum gaps.
4. Follow the cohorts for at least 7 days, ideally 30, and compare total revenue per user. Today's ad revenue can look good while the group loses retention that costs more next week.

Interstitial or rewarded?

Many games now give rewarded ads more of the job, because players choose them and they often earn higher rates per impression. A common approach is to reduce interstitial load for players who regularly watch rewarded videos, or for those who pay. Removing interstitials can also be sold as an in-app purchase. Rewarded vs interstitial playable ads compares the two for advertisers, and rewarded video best practices covers implementation.

For advertisers: making interstitial creative that works

• Assume no one wanted this. The viewer was on their way somewhere else, so the first second has to earn attention. Start with action, not a logo.
• Show the message before the close button appears. With a five-second skip, your hook and offer must both land in that window.
• Make the app obvious, so the person knows what they would be installing. Clear gameplay beats abstract brand imagery.
• Finish with a strong end card. Many viewers skip right to it, so it may be the only part they see. Make its button big and its message simple.
• Consider interactivity. An ad the viewer can play earns attention in a way that a video can only hope for. See how playable ads compare with video.
• Keep it honest and non-tricky. Fake close buttons and misleading controls can break policy and produce useless clicks.

Playable Ads Maker builds playable interstitials and interactive end cards in the browser and handles the packaging differences across 12 ad networks, including the store-exit call each one expects.

Common mistakes

• Showing an ad as soon as the app launches or at the start of a level.
• Triggering an ad when a player taps Play or Next, so the tap seems to have caused it.
• Not preloading, so the ad appears late and lands on the wrong screen.
• Testing frequency by looking at ad revenue for a single day.
• Treating all players alike, when new players and paying players should see far fewer ads.
• Close buttons that are tiny or hidden, which draw accidental clicks that advertisers pay for and users resent.