DevSpeedTools is a small, focused toolbox for the things developers do every day — convert formats, format code, validate syntax, encode data. Every tool runs entirely in your browser. Nothing you paste is uploaded, and you never need an account.
// Why
Why client-side?
Most developer tools either upload your data to a server or show ads everywhere. We chose the harder path: run the tools in JavaScript so your data never leaves your device. It's better for privacy and usually faster too. When you paste a YAML file into our converter, the parsing happens in your browser's JavaScript engine — no network request is made with your data. This means the tools work offline once loaded, process data instantly without server latency, and keep your sensitive configuration files, API keys, and personal data completely private.
// What
What's available now
The initial release covers 45 tools across YAML, JSON, encoding, decoding, formatting, validation, and generation. You can convert YAML to JSON, format messy JSON, decode JWT tokens, generate UUIDs, test regular expressions, look up HTTP status codes, and much more. Every tool is free to use with no signup required.
// How
How it's built
The site is built with Astro for minimal JavaScript on every page. Tool-specific code is loaded only on the page that needs it, so the homepage loads fast while tool pages include only the libraries they require. The design follows a strict design system — minimal surfaces, restrained colour, real monospace. Every interaction is optimised for keyboard-first use with full screen reader support.
Astro generates static HTML at build time, which means the first paint of every page is a plain HTML document with zero JavaScript overhead. The component architecture keeps tool logic isolated — a YAML converter lives in its own module and is never imported by an unrelated page. This island-style approach keeps bundle sizes small and makes it easy to add new tools without slowing down the rest of the site. Performance is measured with Lighthouse and Core Web Vitals on every deploy, and we target a perfect score on the performance audit.