When you share a vault, start a family or name a legacy contact, your device seals a key to the other person’s account. A fingerprint is how you check that the account is really theirs.
What it looks like
Eight groups of five digits, made from the account’s identity key:
48213 90417 55602 13874
26650 71938 04421 68305Compare it
- When you Find someone by their email address, Vallkey shows their fingerprint.
- Ask them to read you the fingerprint Vallkey shows for their own account. It’s under Your fingerprint on any vault’s sharing page.
- If the two match, go on. If they don’t, stop.
Do it in person or on a call, not over the same email or chat you’d use to share.
Do I have to?
No. Vallkey also checks every key against its public key log by itself, and says so under the fingerprint. Comparing fingerprints once adds a check that doesn’t depend on Vallkey’s servers at all, and it protects even the very first time you share.
After the first time
Vallkey remembers the key it saw for each person. If it ever changes, Vallkey refuses to share with them until you compare fingerprints again and choose to trust the new key.
Your own fingerprint stays the same when you change your master password, and when you recover your account.
Last updated October 3, 2026