Decode and inspect JWT tokens from the command line
npm install @lxgicstudios/jwt-decodeDecode and inspect JWT tokens from the command line.
See what's inside your tokens. Check if they're expired. No more jwt.io tabs.
``bashUse directly with npx (recommended)
npx @lxgicstudios/jwt-decode
Usage
bash
Decode a token
npx @lxgicstudios/jwt-decode eyJhbGciOiJIUzI1NiIs...Works with "Bearer " prefix
npx @lxgicstudios/jwt-decode "Bearer eyJhbGci..."Pipe from env var
echo $AUTH_TOKEN | npx @lxgicstudios/jwt-decodeRead from file
npx @lxgicstudios/jwt-decode -f token.txtCheck if expired (for scripts)
npx @lxgicstudios/jwt-decode --check $TOKEN && echo "Valid"
`Example Output
Header
──────
alg: "HS256"
typ: "JWT"Payload
───────
sub: "1234567890"
name: "John Doe"
email: "john@example.com"
iat: 1706547200 (2024-01-29T16:00:00.000Z)
exp: 1706633600 (2024-01-30T16:00:00.000Z)
Status
──────
Valid - expires in 23 hours
Issued: 2024-01-29T16:00:00.000Z
Options
| Option | Description |
|--------|-------------|
|
| Read token from file |
| -c, --claim | Extract specific claim only |
| --header | Show only header |
| --payload | Show only payload |
| --json | Output as JSON |
| --check | Check expiration (exit 1 if expired) |
| -h, --help | Show help |Examples
`bash
Extract user ID
npx @lxgicstudios/jwt-decode -c sub $TOKENGet expiration as JSON
npx @lxgicstudios/jwt-decode --json $TOKEN | jq .expiresInUse in scripts
if npx @lxgicstudios/jwt-decode --check $TOKEN 2>/dev/null; then
echo "Token is valid"
else
echo "Token expired, refreshing..."
fi
`Programmatic API
typescript
import {
decodeJwt,
getJwtExpiration,
getJwtClaim,
isValidJwtStructure
} from '@lxgicstudios/jwt-decode';// Decode full token
const decoded = decodeJwt(token);
console.log(decoded.payload.sub);
console.log(decoded.isExpired);
// Get expiration info
const { isExpired, expiresAt, timeRemaining } = getJwtExpiration(token);
// Extract specific claim
const userId = getJwtClaim(token, 'sub');
// Validate structure
if (isValidJwtStructure(token)) {
// Token is well-formed (doesn't verify signature)
}
``- ✅ Colored, readable output
- ✅ Automatic "Bearer " prefix handling
- ✅ Human-readable expiration times
- ✅ Timestamp conversion
- ✅ Pipe support
- ✅ Script-friendly exit codes
- ✅ JSON output mode
---
Built by LXGIC Studios