hypothesis.sh vs JWT Lens

A free suite of tools for software engineers useful for evaluating, testing, and verifying ideas. Hypothesis allows you to send yourself push notifications, debug webhooks, convert values, and read useful reference guides!

JWT Lens is a fast, private JSON Web Token decoder and verifier for developers — a Safari extension that works entirely on your device. Tap the toolbar icon, paste a token (or grab the text you've selected on the page), and instantly see: • Pretty-printed, color-coded Header and Payload • Human-readable timestamps — exp, iat and nbf shown in your local time with relative phrasing ("expires in 59 minutes") • An at-a-glance expiry badge: valid, expired, or not yet valid • Plain-English descriptions of standard claims (iss, sub, aud, and more) Need to check a signature? JWT Lens verifies HS256/384/512, RS256/384/512, PS256/384/512 and ES256/384/512 using a secret or PEM public key you provide — all computed locally with the system's WebCrypto, never sent anywhere. Privacy by design: • No network requests — ever • No analytics, no tracking, no accounts • Nothing is stored: tokens and keys live only in the popup while you use it Whether you're debugging OAuth / OIDC flows, inspecting a bearer token, or learning how JWTs work, JWT Lens keeps it quick, clear, and completely on-device. Universal app: works in Safari on macOS, iOS and iPadOS.