Tokens are base64 encoded which means the information stored in them can be read by anyone. Don’t send sensitive information in them:
For instance the following JWT:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.PcmVIPbcZl9j7qFzXRAeSyhtuBnHQNMuLHsaG5l804A
Decodes into this:
{"alg":"HS256","typ":"JWT"}{"sub":"1234567890","name":"John Doe","iat":1516239022}Rme>5t
28
JWT’s are sent with a signature that needs to be verified in order for you to trust anything that is sent.