JWT Decoder

This is a small library for decoding a json web token for dart / flutter. Since the header and payload is base64 encoded you can easily know the stored data with no password, you can also know if the token is expired or not.

If you like this library there's a version for Vue here. And for React here

Getting Started

Decode a token

main () {
  String yourToken = "Your JWT";
  Map<String, dynamic> decodedToken = JwtDecoder.decode(yourToken);

  If the token has a valid format, you will get a Map<String, dynamic>
  Your decoded token can look like:
     "sub": "1234567890",
     "name": "Gustavo",
     "iat": 1516239022,
     "exp": 1516239022,
     "randomKey": "something else"

Know if the token is expired

main () {
  String yourToken = "Your JWT";
  bool hasExpired = JwtDecoder.isExpired(yourToken);

  // You will get a true / false response
  // true: if the token is already expired
  // false: if the token is not expired

Get expiration date

main () {
  String yourToken = "Your JWT";
  DateTime expirationDate = JwtDecoder.getExpirationDate(token);

  // 2025-01-13 13:04:18.000

You can know how old your token is

// Token payload must include an 'iat' field
main () {
  String yourToken = "Your JWT";
  Duration tokenTime = JwtDecoder.getTokenTime(token);

  // 15