JWT (JSON Web Token)
Definition
A compact, URL-safe token format used for securely transmitting information between parties as a JSON object, commonly used for authentication.
A JSON Web Token is a self-contained token that securely represents claims between two parties. It consists of three parts separated by dots: a header (algorithm and token type), a payload (claims or data), and a signature (verification mechanism). Each part is Base64URL encoded.
JWTs are widely used for authentication in web applications. After a user logs in, the server issues a JWT containing the user's identity and permissions. The client includes this token in subsequent API requests, and the server verifies the signature to authenticate the user without querying a database.
JWTs are stateless (the server does not need to store session data), making them ideal for distributed systems and microservices. However, they have trade-offs: tokens cannot be individually revoked without additional infrastructure, and sensitive data should not be stored in the payload since it is only encoded, not encrypted.
Related Calculators
Related Terms
JSON (JavaScript Object Notation)
techA lightweight data interchange format that is easy for humans to read and write and easy for machines to parse and generate.
API (Application Programming Interface)
techA set of rules and protocols that allows different software applications to communicate with each other and share data or functionality.
Encryption
techThe process of converting readable data (plaintext) into an unreadable format (ciphertext) using an algorithm and key, protecting it from unauthorized access.
Base64
techA binary-to-text encoding scheme that converts binary data into a string of ASCII characters, commonly used for embedding data in web pages and emails.
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