Create and Sign JSON Web Tokens Online in Real-Time
Generate secure JWT tokens with live preview. Perfect for developers, API testing, and authentication workflows.
Generate a token to see its decoded information here.
A JWT Encoder is a powerful online tool that allows developers to create and sign JSON Web Tokens (JWT) in real-time. JWTs are compact, URL-safe tokens used for securely transmitting information between parties as a JSON object. This tool simplifies the process of generating JWTs for testing, development, and debugging purposes.
Create JWT tokens instantly with live preview functionality
Sign tokens with HMAC algorithms (HS256, HS384, HS512)
Perfect for API testing, authentication workflows, and debugging
JSON Web Tokens (JWT) are an open, industry standard (RFC 7519) method for representing claims securely between two parties. JWTs are commonly used for authentication and information exchange in web applications and APIs.
JWT tokens consist of three parts separated by dots (.), which are:
Contains metadata about the token, including the signing algorithm
Contains the claims, which are statements about an entity and additional data
Ensures the token hasn't been tampered with and validates authenticity
Each part of a JWT token serves a specific purpose in the authentication and authorization process:
| Component | Description | Example |
|---|---|---|
| Header | Contains token type and signing algorithm | {"alg": "HS256", "typ": "JWT"} |
| Payload | Contains claims about the entity | {"sub": "1234567890", "name": "John Doe", "iat": 1516239022} |
| Signature | Verifies token authenticity | HMACSHA256(base64UrlEncode(header) + "." + base64UrlEncode(payload), secret) |
When working with JWT tokens, always follow these security guidelines:
JWT tokens can contain various claims that provide information about the token and its subject:
| Claim | Name | Description |
|---|---|---|
iss |
Issuer | Identifies the principal that issued the JWT |
sub |
Subject | Identifies the principal that is the subject of the JWT |
aud |
Audience | Identifies the recipients that the JWT is intended for |
exp |
Expiration Time | Identifies the expiration time on or after which the JWT must not be accepted |
nbf |
Not Before | Identifies the time before which the JWT must not be accepted |
iat |
Issued At | Identifies the time at which the JWT was issued |
jti |
JWT ID | Provides a unique identifier for the JWT |
Creating JWT tokens with our online encoder is simple and straightforward:
Enter the JSON data you want to include in the token payload. This typically includes user information, permissions, and expiration details.
Select the appropriate HMAC algorithm (HS256, HS384, or HS512) based on your security requirements.
Provide a strong secret key that will be used to sign the token. Keep this key secure and never expose it in client-side code.
Click the "Generate Token" button to create your signed JWT token. The result will appear in the output area.
Copy the generated token and use it in your applications, API requests, or testing scenarios.
JWT tokens are widely used for securing REST APIs. When a user logs in, the server generates a JWT token that the client includes in the Authorization header of subsequent requests.
JWT tokens enable seamless authentication across multiple related but independent software systems, providing a unified login experience.
JWTs can be used to securely transmit information between parties, with the signature ensuring the information hasn't been tampered with.
This JWT Encoder tool is built using modern web technologies to provide a fast and reliable token generation experience:
Our JWT Encoder supports the following HMAC signing algorithms:
| Algorithm | Description | Security Level |
|---|---|---|
| HS256 | HMAC using SHA-256 | High |
| HS384 | HMAC using SHA-384 | Very High |
| HS512 | HMAC using SHA-512 | Extremely High |
JWT is a token format, while OAuth is an authorization framework. JWT can be used as a token format within OAuth flows, but they serve different purposes. OAuth defines how tokens are issued and used, while JWT defines the structure and content of the tokens themselves.
JWT tokens are secure when implemented correctly. The signature ensures token integrity, but the payload is only base64 encoded (not encrypted). Never include sensitive information in the payload, and always use HTTPS for transmission.
JWT tokens cannot be revoked once issued because they are stateless. To handle token revocation, implement a token blacklist or use shorter expiration times. For critical applications, consider using reference tokens instead.
Use a cryptographically secure random string that is at least 256 bits (32 characters) long. Avoid using easily guessable information like passwords or common phrases. Consider using a password generator to create strong secret keys.
Follow these guidelines to ensure secure and effective JWT implementation:
Our online JWT Encoder tool offers several advantages over other solutions:
The JWT Encoder is an essential tool for developers working with authentication systems, API development, and security testing. By providing a simple interface for creating and signing JWT tokens, it streamlines the development process and enables rapid prototyping and testing of authentication workflows.
Whether you're building a new web application, testing an existing API, or learning about JWT authentication, this tool provides everything you need to generate secure tokens quickly and efficiently. Remember to always follow security best practices when implementing JWT in production environments.
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