About

Single purpose developer utilities, kept small enough to load instantly and simple enough to trust.

Nothing leaves your browser

Every tool runs on the page you are looking at, as plain JavaScript, or for the Regular Expression Tester's PCRE, Go, Rust, sed and grep flavors, as those engines compiled to WebAssembly and loaded from this site. There is no API behind them, so what you paste in is never uploaded, stored, or logged. The pages are static files; the only state kept, and only in your own browser, is whether you left the sidebar collapsed, which zones and clock World Time Zones starts with, the settings the Regular Expression Tester was last left with, and the Spreadsheet's list of recent sheets.

One tool can fetch: the Spreadsheet's Open from a web address reads the file you name, straight from that site into your browser. Nothing is sent back, and every other tool makes no network request at all.

Getting around

Press / anywhere to open the command palette and jump straight to a tool.