What is a JWT (JSON Web Token)?

A JWT is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three Base64-encoded parts: Header (algorithm and type), Payload (claims/data), and Signature (verification). JWTs are commonly used for authentication and API authorization.

Is this JWT Decoder free and safe?

Yes, completely free with no signup. It's also 100% safe - all decoding happens in your browser using JavaScript. Your tokens never leave your device and are never sent to any server. Perfect for debugging sensitive authentication tokens.

Can I decode a JWT without the secret key?

Yes! JWT headers and payloads are only Base64-encoded, not encrypted. Anyone can decode and read them. The signature requires the secret to verify, but not to read. This is why you should never put sensitive data in JWT payloads.

What information is in a JWT payload?

Common claims include: sub (subject/user ID), iat (issued at timestamp), exp (expiration timestamp), iss (issuer), aud (audience), and custom claims like user roles or permissions. Our decoder shows all claims with human-readable timestamps.

How do I check if a JWT is expired?

Look at the 'exp' (expiration) claim in the decoded payload. Our tool automatically converts Unix timestamps to readable dates and highlights if the token is expired. The 'iat' (issued at) shows when it was created.

What JWT algorithms are supported?

Common algorithms: HS256/HS384/HS512 (HMAC with SHA), RS256/RS384/RS512 (RSA), ES256/ES384/ES512 (ECDSA), and 'none' (unsigned). Our decoder identifies the algorithm from the header. RS256 is most common for public APIs.

Why are there three parts separated by dots?

The three parts are: 1) Header - specifies algorithm and token type, 2) Payload - contains the claims (data), 3) Signature - verifies the token wasn't tampered with. Format: header.payload.signature, each Base64URL encoded.

Is JWT the same as encryption?

No! Standard JWTs (JWS) are signed but NOT encrypted - anyone can read the payload. For encrypted tokens, use JWE (JSON Web Encryption). Never put passwords, credit card numbers, or sensitive data in regular JWT payloads.

JWT Decoder

Decode and inspect JSON Web Tokens with expiry validation

JWT Token0 chars

JWT Settings

Live Decode

Decode as you type

Show Timestamps

Display iat/exp as dates

JWT Structure

HeaderAlgorithm & token type

PayloadClaims & data

SignatureVerification hash

Common Claims

iss - Issuer

sub - Subject

aud - Audience

exp - Expiration time

iat - Issued at

nbf - Not before

jti - JWT ID

This tool only decodes JWTs. It cannot verify signatures. Never paste production tokens with sensitive data.

Tool Capabilities

Client-Side (Browser)

Files never leave your device

Decode JWT tokens (header, payload, signature)
Display expiration & issued times
Validate token structure
Copy decoded sections
Pretty-print JSON payload

Requires Server-Side

Not available — would need cloud processing

Verify JWT signature (requires secret/public key)
Token generation with signing
JWKS endpoint validation
Token revocation checking

JWT signature verification and token generation require secret keys that should never be exposed in the browser.

Features

Decode JWT

Parse and display JWT contents instantly

View Header

See algorithm and token type

View Payload

Inspect claims and custom data

Expiration Check

Automatic expiry detection with countdown

Timestamp Display

Human-readable date/time for iat/exp

100% Client-Side

Your tokens never leave your browser

TL;DR - Free JWT Decoder

Decode and inspect JSON Web Tokens instantly. View header, payload, and signature. Check expiration status with automatic countdown. 100% client-side - your tokens never leave your browser.

Expiry validationLive decodeTimestamp display100% private

JumpTools vs Other JWT Decoders

How does our JWT decoder compare to alternatives?

Feature	JumpTools	JWT.io	JWT.ms
Price	Free	Free	Free
Privacy	100% client-side	Client-side	Client-side
Expiry countdown	Live countdown	Static display	Yes
Signature verification	Decode only	Yes (with secret)	No
Timestamp conversion	Auto human-readable	Manual	Auto
Claims reference	Built-in guide	Yes	Limited
Live decode	As you type	As you type	As you type
Clean UI	Minimal, focused	Feature-rich	Microsoft themed

Comparison as of February 2026. For signature verification, use JWT.io with your secret key.

Frequently Asked Questions

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Loading tool...

JWT Decoder

Decode and inspect JSON Web Tokens with expiry validation

JWT Token0 chars

JWT Settings

Live Decode

Decode as you type

Show Timestamps

Display iat/exp as dates

JWT Structure

HeaderAlgorithm & token type

PayloadClaims & data

SignatureVerification hash

Common Claims

iss - Issuer

sub - Subject

aud - Audience

exp - Expiration time

iat - Issued at

nbf - Not before

jti - JWT ID

This tool only decodes JWTs. It cannot verify signatures. Never paste production tokens with sensitive data.

Tool Capabilities

Client-Side (Browser)

Files never leave your device

Decode JWT tokens (header, payload, signature)
Display expiration & issued times
Validate token structure
Copy decoded sections
Pretty-print JSON payload

Requires Server-Side

Not available — would need cloud processing

Verify JWT signature (requires secret/public key)
Token generation with signing
JWKS endpoint validation
Token revocation checking

JWT signature verification and token generation require secret keys that should never be exposed in the browser.

Features

Decode JWT

Parse and display JWT contents instantly

View Header

See algorithm and token type

View Payload

Inspect claims and custom data

Expiration Check

Automatic expiry detection with countdown

Timestamp Display

Human-readable date/time for iat/exp

100% Client-Side

Your tokens never leave your browser

TL;DR - Free JWT Decoder

Decode and inspect JSON Web Tokens instantly. View header, payload, and signature. Check expiration status with automatic countdown. 100% client-side - your tokens never leave your browser.

Expiry validationLive decodeTimestamp display100% private

JumpTools vs Other JWT Decoders

How does our JWT decoder compare to alternatives?

Feature	JumpTools	JWT.io	JWT.ms
Price	Free	Free	Free
Privacy	100% client-side	Client-side	Client-side
Expiry countdown	Live countdown	Static display	Yes
Signature verification	Decode only	Yes (with secret)	No
Timestamp conversion	Auto human-readable	Manual	Auto
Claims reference	Built-in guide	Yes	Limited
Live decode	As you type	As you type	As you type
Clean UI	Minimal, focused	Feature-rich	Microsoft themed

Comparison as of February 2026. For signature verification, use JWT.io with your secret key.

Frequently Asked Questions

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Free cron expression generator. Build crontab schedules visually, get human-readable descriptions & next run times. No signup. 100% client-side.

HTML Encoder

Free HTML encoder & decoder. Escape special characters to HTML entities, prevent XSS. Safely encode &, <, >, quotes. 100% client-side. No signup needed.

JSON Formatter

Free JSON formatter & validator. Beautify, minify, validate JSON with syntax highlighting. 100% client-side, no upload. Used by 100K+ devs. Try instantly.

Hash Generator

Free hash generator. Generate SHA-256, SHA-512, SHA-1 hashes from text or files. File checksum verification, HMAC support. 100% client-side. No signup.

Image Compressor

Free image compressor. Reduce JPG, PNG, WebP, GIF size up to 80% without quality loss. No upload to server - 100% private. Bulk compress. Try now.