# Safety numbers

Check that nobody sits between you and the person you talk to.

## Compare the numbers

1. Open the chat and its details.
2. Open the safety number. You both see the same 60 digits.
3. Compare them in person or on a call. If they match, your chat is private.

## When a key changes

Your app remembers each contact’s key. If it changes, for example after they reinstall and start fresh, the chat shows a warning so you can compare again.

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Source: https://chat.ababilx.com/docs/safety-numbers
Last updated: 2026-09-05