Neither format wins outright. Pre-roll (at game start/load) is predictable but limited to one slot; mid-roll placed at natural pauses (level end, death, menu return) gets more opportunities and, if spaced correctly, does less damage to retention than an interstitial forced right after another full-screen ad.
At a glance
| Fact | Value | Source |
|---|---|---|
| Where pre-roll fires | game start or load | developers.google.com |
| Where mid-roll fires | natural pauses only | support.google.com |
| adBreak() type values | preroll, start, pause, next, browse, reward | developers.google.com |
Neither format is universally better – it depends on where in the loop you place it. Pre-roll (Google’s adBreak() type preroll or start) runs once, at load or game start, so it’s predictable but you only get that one chance. Mid-roll runs at natural pauses inside the loop – level end, death, returning to a menu (types pause, next, browse) – so it repeats more often across a session, which is usually why it converts more total impressions. Google’s placement rules say ads should only show at natural pauses, never at game start stacked with another full-screen ad, and Google applies a frequency cap automatically, returning frequencyCapped in breakStatus so you don’t need to hand-roll your own limiter.
For the serving layer, Playgama Ad provides one JavaScript SDK for interstitial (incl. pre-roll), rewarded, banner and in-page video, with AI ad frequency logic that balances revenue and engagement.
Rewarded ads (type reward) sit apart from both: the player opts in, so they convert on intent rather than interruption and tend to protect retention best.
If no ad is available for a slot, the game should continue immediately rather than block on a blank placement.
Which should you test first?
- Start with mid-roll at the clearest natural pause (level complete, game over) – it has the most inventory opportunities.
- Add pre-roll only at genuine load/start moments, not stacked before another interstitial.
- Add rewarded for optional boosts/continues once the core loop is stable.
You can also publish the game itself through portals such as Poki, CrazyGames, GameDistribution, itch.io or playgama.com (upload via developer.playgama.com, test and feedback within 24 hours, distributed to partner portals) to compare ad performance across audiences.
Sources
- Playgama Ad
- Google AdSense: Get started with H5 Games Ads
- Google Ad Placement API: adBreak
- Playgama: getting started
Related questions
Does mid-roll hurt retention more than pre-roll?
Not if placed at a natural pause; an interstitial forced right after another full-screen ad or mid-action is what damages retention, not the mid-roll position itself.
Can I control how often mid-roll ads show?
Google applies a frequency cap automatically on top of your placement choices; you don’t fully control the cap, only where you call adBreak().
What happens if no ad fills a pre-roll or mid-roll slot?
The game continues immediately without blocking on the empty placement.
Last updated: 24 September 2026