Tokens
How to identify and crack a JSON Web Token (JWT) hash
Identify a JSON Web Token (JWT) hash and crack it with ready-to-run hashcat and John the Ripper commands. Fast on a GPU.
JSON Web Token (JWT) is a token hash type. It is fast and typically unsalted, which makes weak passwords recoverable quickly on consumer GPU hardware. This page shows how to recognise it and the exact commands to attack it.
All identification runs locally in WebAssembly. The commands below write the hash to a local file on your machine — nothing is sent to this site.
Identifying the hash
The hash identifier on the home page detects JSON Web Token (JWT) entirely in your browser — your hash is never uploaded. A typical example looks like this:
eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0In0.dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk
Cracking JSON Web Token (JWT) with hashcat
Save the hash to a file and run hashcat in mode -m 16500. Start with a wordlist such as rockyou.txt:
echo 'eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0In0.dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk' > hash.txt && hashcat -m 16500 hash.txt /usr/share/wordlists/rockyou.txt
Add a rule set to mutate dictionary words (capitalisation, leetspeak, appended digits) and dramatically widen coverage:
echo 'eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0In0.dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk' > hash.txt && hashcat -m 16500 hash.txt /usr/share/wordlists/rockyou.txt -r /usr/share/hashcat/rules/best64.rule