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JWT Libraries by Language

Production-grade JWT libraries for every major language, with notes on which to pick and when. Each card links to a full sign-and-verify guide for that language.

How to choose a JWT library

Pick the library that matches your algorithm needs and your framework. For HS256/RS256 only, the simplest library in your language is fine (jsonwebtoken, PyJWT, golang-jwt, firebase/php-jwt). For EdDSA, JWE, or JWKS verification with built-in caching, use the JOSE-spec library (jose, go-jose) or a JWKS helper (keyfunc, PyJWKClient). Inside Spring Boot, Spring Security's OAuth2 Resource Server handles verification declaratively: use jjwt only when you need to sign tokens or verify outside Spring. See the EdDSA library-support matrix for per-language EdDSA support.

What every JWT library must do

Regardless of language, a correct JWT verification call hardcodes the algorithm (never reads it from the token header), verifies the signature against the right key, and validates exp, iss, and aud. Most libraries do signature and exp by default but make iss and aud opt-in: always pass your expected issuer and audience explicitly. See the claims reference and the security guide for the rules every library expects you to enforce.