About PasteKit

Developers paste configuration, API responses, queries and logs into online formatters dozens of times a week. Many of those tools are slow, cluttered with ads inside the work area, and send what you paste to their servers. In November 2025, researchers found more than 80,000 saved pastes from two of the most popular formatter sites containing credentials, cloud keys and private keys.

PasteKit is built on one promise: paste on the left, correct pretty output on the right, instantly, with no upload. It formats58 formats and converts between 48 pairs, entirely in your browser, with WebAssembly ports of the same formatters you run locally — Ruff, gofmt, clang-format, rustfmt, Prettier and more.

Principles

• Private by construction. No server receives your input, enforced by a published Content Security Policy.
• Correct. Every engine is tested for idempotency, lossless round trips, located errors and fuzzed input.
• Fast. Formatting runs in a Web Worker; large files never freeze the page.
• Helpful errors. Line, column and a plain-English explanation instead of a blank screen.
• Ads stay out of the way. Never inside the editor, never next to the Copy and Format buttons.

Questions or suggestions? Get in touch.