Developer Tools
Format, convert, validate and test — without pasting your data into someone else's server.
- Base64 Encoder & DecoderBoth directions, Unicode-safe, with the URL-safe alphabet when you need it.Runs in your browser
- JSON FormatterFormat, validate and inspect JSON — with an error that points at the character.Runs in your browser
- JWT DecoderRead a token’s header and claims, and see what it says about itself. Decoding, not verification.Runs in your browser
- Regex TesterTest a pattern against real text, with matches highlighted and a hard stop on runaway backtracking.Runs in your browser
- Cron ParserRead a cron expression in plain English, and see exactly when it will next fire.Runs in your browser
- Unix Timestamp ConverterTimestamps to dates and back, with the unit worked out for you and stated.Runs in your browser
- URL Encoder & DecoderPercent-encoding in all three flavours, side by side, so you can see which one you want.Runs in your browser
- UUID GeneratorGenerate v4 or time-ordered v7 UUIDs, and inspect any UUID you already have.Runs in your browser
What these tools have in common
The everyday utilities: reformat a response, convert between two formats a system insists on, work out what a cron expression actually does, check a regex against real input.
The reason to care where these run is boring but real. The JSON you are debugging is usually a production payload, and it usually has a customer in it. Every tool in this section does its work in your browser, so that payload stays on your machine — which also means they keep working with no network at all.
The regex tester runs your pattern in a Web Worker with a hard timeout, so a catastrophically backtracking expression fails the way it should instead of freezing the tab.