JWT Generator

Build a JWT from an editable header and payload, sign it with HMAC, RSA, ECDSA, or RSA-PSS, and copy the result (entirely client-side).

Decode Generate

Use only on systems you own or are explicitly authorized to test.

Scenario presets

Algorithm

HMAC secret

Strength256 bits

Quick strength:

Standard = letters + numbers only. Enhanced = adds special characters. Strength sets the generated secret's target entropy (default 256 bits). Only the start/end are shown by default. Click into the field or use "Show" above to see it in full.

Header

Payload

Quick-add claims

iat

exp

nbf

expired 20663d 4h ago

exp is in the past (1970-01-01T01:00:00.000Z) — this token is already expired.

Combined Copy Format

Header

Payload

{
  "alg": "HS256",
  "typ": "JWT"
}
{
  "sub": "user-1234",
  "iat": 0,
  "exp": 3600
}

Decode & verify an existing token