Crumb: Cookie Editor, Header Rules & JWT Decoder

Edit, search, import and export cookies, apply per-URL header and cookie rules with profiles, and decode JWTs. Local only.

Crumb is a cookie editor and request debugging helper that lives in your toolbar. What it does - List all cookies sent to the current tab and search them by name, value or domain - Create, edit and delete cookies, including Domain, Path, expiry, SameSite, Secure and HttpOnly - Import and export cookies as JSON, Netscape or Header string (the format is detected on import) - Delete all cookies for the current tab in one step - Add or remove custom request and response headers - Append request Cookie values, add or expire response Set-Cookie values with Domain, Path, SameSite, Max-Age and Secure - Scope each rule to a URL or URL pattern, add a comment, and switch rules on or off one by one - Group rules into local profiles, activate a profile, and import or export profiles as JSON - Pause or resume every rule with one master toggle or the Alt+Shift+R shortcut - See how many rules were applied on the toolbar badge - Decode JWTs from a pasted token or from your cookies (signature is not verified) - Light and dark theme that follows your system, plus an advanced mode and optional extra columns Private by design - No analytics, no tracking, no accounts - No remote code and no external servers - Rules and settings are stored on your device - Access is requested per site, on demand