Glossary / Developer basics
Glossary · Developer basics · checked Oct 24, 2026
JWT (JSON Web Token)
Short answerA JWT is a signed token in three base64url parts, header.payload.signature, defined in RFC 7519. The payload is readable by anyone; the signature only proves who issued it.
Why it matters
Never put secrets in a JWT payload, and always verify the signature and the exp claim on the server.
Our number
Our JWT decoder decodes a token locally, nothing is sent anywhere. App Store Connect API keys sign JWTs the same way.
Go deeper on this site
Where it shows up here
It appears on 9 pages of this site: 4 Free tools, 2 Articles, 2 Guides, 1 The Manual. A few to start with:
- iOS development on Windows: the complete guide (21 apps, no Mac)
- App development.
- The Manual.
- Step-by-step guides.
- How to create an App Store Connect API key and use it in CI
- Cron expression translator.
- JWT decoder.
Sources
- RFC 7519, JSON Web Token: www.rfc-editor.org/rfc/rfc7519 (checked Oct 24, 2026)
Related terms
Up next
Go deeperJWT decoderThe page on this site that does the most with this term.Read it next →Also worth your time
Did this answer your question?