How many extra testers to recruit for a closed test

Google's help page says at least 12 testers must be opted in when you apply, and they must have been opted in "continuously for the preceding 14 days." Opting out and back in only counts if the 14 days are consecutive. Source: Play Console Help, retrieved 2026-10-24.

So 12 is the floor. Anyone who leaves, or never really joins, puts you under it. A buffer protects you.

No magic number

We don't have measured drop-out rates and won't invent one. Your own risk depends on how you recruit (people you know vs. strangers), how hard installing is (account issues, paid app), and how long you stay in touch. Use a method with stated assumptions instead.

A simple method

1. Target: T = 12 testers opted in on the day you apply.
2. Guess your drop-out share: d, between 0 and 1. Pick it from your own situation. Be cautious if testers are strangers or the app is hard to install. Example: d = 0.25 means you expect one in four to leave.
3. Recruit: N = T / (1 - d), rounded up.
4. Add a replace window: plan to replace leavers early. A replacement who joins late must still complete 14 days in a row, so late replacements can delay your application date.

Example (not a forecast): T = 12, d = 0.25 → N = 12 / 0.75 = 16. Recruit 16 people. With d = 0.5, N = 24.

Adjust after the first days

• After days 1-3, count how many actually opted in and installed. If you're below N, recruit more now.
• If your first assumption was too low, raise d and top up.
• Track opt-ins in your log, see what to do during the 14 days.

Quality beats count

Twelve testers who open the app and write real feedback are worth more than twenty who never install. The production form asks how engaged testers were, see answering the production access form. Ways to keep people active: keep testers engaged.

Related article: closed test testers dropped out.

The formula in short

Inputs: required testers (default 12), expected drop-out share. Output: testers to recruit = required / (1 - drop-out), rounded up. Limit: it is only as good as your drop-out guess.

With AppReviewX

Test rounds for Google Play are built for 12 testers over 14 days in a row, for Android apps. Feedback is private and structured; 1 feedback = 1 credit; new accounts start with 0 credits. Join a test round

Related: Google Play closed testing hub, see whether testers use your app