JSON formatter, text diff checker, base64 encoder, UUID generator, markdown editor, and more. Zero install, works offline.
Every developer has a collection of bookmarklets and random websites they use for quick utilities: format some JSON, diff two configs, generate a UUID, encode something in base64.
Most of these tools send your data to a server. I built 10 developer utility tools that never leave your browser.
The Stack (or Lack Thereof)
Each tool is one HTML file. No React, no Vue, no build step. Vanilla JS + browser APIs:
crypto.getRandomValues() for UUIDs, random numbers, secure passwords
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