What the account and sync send

The apps send account and sync data only to the server you entered, and nothing before you sign in. See also What leaves your device.

What’s sent

• Signing up or in sends your email, name, public keys, key-derivation settings, and this device’s id, name (the computer’s host name, or the phone’s maker and model) and platform. Your password isn’t sent: a key derived from it (the auth key) is, and your encryption keys only wrapped with keys the server doesn’t have.
• While signed in, every change to your hosts, groups, keys, snippets and settings goes as an encrypted blob, with its id, vault, type, revision, key version and deleted flag in plain text. Sync runs at start, after each change and every minute, and a WebSocket brings changes at once.
• Keys and identities sync encrypted unless Settings › Security › Sync keys and identities is off.
• Session logs upload encrypted only with Settings › Logs › Sync session logs, which is off by default.
• For a team, the owner’s app sends the signed member list at each change: team id and name, members’ ids and key fingerprints, vault ids, key versions and access, and its policies in plain text. Members’ apps send signed reports of the policies their device applies, without item contents or host addresses.
• Team presence sends the ids of team-vault hosts you have open, never personal hosts. Turn it off with Settings › Security › Show my activity to my team.
• Verifying your email asks the server to mail a code, then sends the code you type.

What the server stores

The server stores in plain text your email, name, handle, public keys, devices, passkeys’ public keys, team names and members, signed member lists, invites, a team’s SAML settings and each item’s metadata. Everything else (item contents, logs, vault names, wrapped keys, the two-factor secret) is encrypted or hashed.

How it’s encrypted: How the end-to-end encryption works.