Developer Toolkit
Convert JSON to YAML and CSV (and back), test regular expressions live, and translate Unix timestamps — the data-wrangling workbench, running entirely in your browser.
All processing happens in your browser — nothing you paste is stored or sent anywhere. For encode/decode and hashing, see our sister site codedecode.dev.
The converters
Paste JSON and get clean YAML for config files, or a CSV ready for any spreadsheet. Going the other way, CSV becomes a JSON array of objects with the header row as keys — quoted fields, embedded commas, and multi-line cells handled correctly, which is where naive converters fall over.
The YAML output quotes the values that famously bite people — strings like no, on, and 1.0 that YAML parsers silently reinterpret as booleans and numbers. Our guide on the "Norway problem" below explains why that matters more than it sounds.
The regex tester
Type a pattern, flags, and test text, and see every match with its position and capture groups. No cryptic silence when the pattern is invalid — you get the actual error. It uses JavaScript regex syntax, the dialect that runs in browsers and Node, which covers most patterns you will meet in the wild.
Timestamps without the mental math
The current Unix time ticks live at the top. Paste any epoch — seconds or milliseconds, auto-detected — and get ISO 8601 UTC plus your local time. Paste a human date and get the epoch back. It is the conversion every developer does weekly and nobody does in their head.
Frequently asked questions
How is this different from codedecode.dev?
Sister sites, different jobs. codedecode.dev handles encoding — Base64, URL escaping, hashes, UUIDs. This site handles data shape — converting between JSON, YAML, and CSV, testing regex, and translating timestamps. Between the two, the daily developer toolbox is covered.
Why did my CSV numbers become strings in the JSON?
CSV has no types — everything in it is text, and guessing types is how ZIP codes lose their leading zeros. We keep values as strings and let you cast the fields you know are numeric. Deliberate, if slightly annoying.
Is my data uploaded anywhere?
No. Conversion, regex matching, and timestamp math all run locally in your browser. The page works offline once loaded.