Swift implementation of JSON Web Token (JWT).
Swift C
Clone or download


JSON Web Token

Build Status

Swift implementation of JSON Web Token.


Swift Pacakage Manager is the recommended installation method for JSONWebToken, CocoaPods is also supported.

pod 'JSONWebToken'

NOTE: Carthage may be supported, however support will not be provided for this installation method, use at your own risk if you know how it works.


import JWT

Encoding a claim

JWT.encode(claims: ["my": "payload"], algorithm: .hs256("secret".data(using: .utf8)!))

Encoding a claim set

var claims = ClaimSet()
claims.issuer = "fuller.li"
claims.issuedAt = Date()
claims["custom"] = "Hi"

JWT.encode(claims: claims, algorithm: .hs256("secret".data(using: .utf8)!))

Building a JWT with the builder pattern

JWT.encode(.hs256("secret".data(using: .utf8))) { builder in
  builder.issuer = "fuller.li"
  builder.issuedAt = Date()
  builder["custom"] = "Hi"

Decoding a JWT

When decoding a JWT, you must supply one or more algorithms and keys.

do {
  let claims: ClaimSet = try JWT.decode("eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.e30.2_8pWJfyPup0YwOXK7g9Dn0cF1E3pdn299t4hSeJy5w", algorithm: .hs256("secret".data(using: .utf8)!))
} catch {
  print("Failed to decode JWT: \(error)")

When the JWT may be signed with one out of many algorithms or keys:

try JWT.decode("eyJh...5w", algorithms: [
  .hs256("secret".data(using: .utf8)!),
  .hs256("secret2".data(using: .utf8)!),
  .hs512("secure".data(using: .utf8)!)

You might also want to give your iat, exp and nbf checks some kind of leeway to account for skewed clocks. You can do this by passing a leeway parameter like this:

try JWT.decode("eyJh...5w", algorithm: .hs256("secret".data(using: .utf8)!), leeway: 10)

Supported claims

The library supports validating the following claims:

  • Issuer (iss) Claim
  • Expiration Time (exp) Claim
  • Not Before (nbf) Claim
  • Issued At (iat) Claim
  • Audience (aud) Claim


This library supports the following algorithms:

  • none - Unsecured JWTs
  • hs256 - HMAC using SHA-256 hash algorithm (default)
  • hs384 - HMAC using SHA-384 hash algorithm
  • hs512 - HMAC using SHA-512 hash algorithm


JSONWebToken is licensed under the BSD license. See LICENSE for more info.