Google Chrome allows you to encrypt all your synced data (passwords, bookmarks, history) using a custom “Sync Passphrase.” This is a master password that is completely separate from your main Google Account password. Google specifically states that if you lose this passphrase, they cannot recover it, and you will lose all your synced data.
However, if you are currently logged into a computer where Chrome is actively syncing, Chrome actually stores a hashed version of this passphrase locally in its internal database. While you cannot extract the raw text password, you can safely extract the cryptographic hash. If your passphrase was relatively simple, you can run this hash through offline cracking software to recover your lost password.
How to Safely Extract the Google Chrome Sync Passphrase Hash
You must use a third-party SQLite database viewer to read Chrome’s internal “Web Data” file.
Warning: Do not attempt to edit this file while Chrome is running, or you will corrupt your browser profile.
- Close the Google Chrome browser completely.
- Open File Explorer (Windows Key + E) and navigate to the following path:
%LocalAppData%\Google\Chrome\User Data\Default - Scroll down and find a file named exactly Web Data (it has no file extension).
- Copy this file and paste it onto your Desktop for safety.
- Download a free, open-source tool called DB Browser for SQLite and install it.
- Open DB Browser, click Open Database, and select the copied `Web Data` file on your Desktop.
- Click on the Browse Data tab at the top.
- In the “Table” drop-down menu, select token_service.
Look for the row labeled sync_encryption_key. The massive string of random characters next to it is the cryptographic hash of your Sync Passphrase. You can extract this string and feed it into specialized recovery software (like Hashcat) to attempt to brute-force and recover your forgotten passphrase, saving your encrypted cloud data from permanent deletion.