DevTul – 12 Dev Tools, 100% Local

100% local processing is exactly what developers need for sensitive JWT and config data. No signup, no network overhead, and offline capability makes this a fantastic daily bookmark!

Decoding JWTs locally is the right call, since pasting production tokens into random online decoders is a real risk. The keyboard shortcut to search tools is handy too. It would be great if the JWT tool could also flag expired tokens by comparing the exp claim to the current time, and a shareable state via the URL hash (never sent to a server) would help with team debugging.

Running everything locally with offline support is a strong selling point for tools like the JWT decoder, since people paste sensitive tokens into those. The visual tree view for JSON/YAML looks handy too. Do you plan to add a diff for JSON structures rather than only line and word text diff?

Tried the cron generator, and the list of next trigger times is the part I always want and most generators skip. One request: it only shows browser local time. GitHub Actions and most cloud schedulers run in UTC, so a UTC toggle would save me the mental math. I'm in Poland, so I'm off by one or two hours depending on DST.

Decoding JWTs locally is the right call, since pasting production tokens into random online decoders is a real risk. The keyboard shortcut to search tools is handy too. It would be great if the JWT tool could also flag expired tokens by comparing the exp claim to the current time, and a shareable state via the URL hash (never sent to a server) would help with team debugging.

Really like that everything is parsed locally, especially for the JWT decoder. Pasting tokens into random online decoders has always felt risky, so this is a genuinely useful angle. Does it also work as a PWA so the tools are available offline after the first visit? Congrats on the launch!

Running the JWT decoder and HS256 signature check entirely in the browser is a good fit for developers who don't want to paste production tokens into a random site. Would you consider adding RS256/ES256 verification with a pasted public key or JWKS, since most real-world tokens aren't HS256?

Question about the regex tester: since it runs in the browser, I assume it uses the JavaScript regex flavor. Do you show that anywhere? Lookbehind, named groups and flags behave a bit differently in PCRE or Python, so a small flavor hint would help when testing patterns meant for a backend.

Decoding JWTs entirely in the browser is a nice touch, since people often paste production tokens into these tools. A small inline reminder that decoding does not verify a token, plus a warning when the payload shows an expired exp claim or alg set to none, would make the JWT tool teach good practice. Would you also add a way to confirm that no network requests are made, like a visible offline badge?

For the local JSON/YAML viewer and regex tester, is the expensive work isolated in a Web Worker? A cancel control and an input-size warning would be useful safeguards when someone pastes a very large configuration or tests a pattern that can block the browser tab.

I really like that the Base64, hash and UUID tools all run locally and that pressing "/" jumps straight to any tool, which makes it a quick everyday bookmark. One friendly suggestion: a "copy as curl/code snippet" option for results like the regex tester or cron builder could save a few more steps.

Local-only and offline is exactly right for this kind of utility. Pasting a JWT or a config into some random online tool always makes me nervous, so keeping it all in the browser is the real selling point here. The visual JSON tree is a nice touch too.

Running everything locally is a strong selling point for developers who paste tokens or customer payloads into online formatters. Can you say how the offline mode works in practice, for example whether a service worker caches all 12 tools after the first visit or only the ones already opened? I would also like to know if the JWT decoder explicitly avoids sending the token anywhere, since that is the check most people want before trusting it.