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Free client-side developer toolkit

Developer tools
that stay in your browser

Format data, decode tokens, convert files, and explore package indexes—without uploading secrets to a server. Browse our live catalog or jump straight into the workflow you need.

990+ in catalog10 categories
100% Client-Side SandboxClient-Side ExecutionQuick open⌘K
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Popular tools

High-traffic utilities developers open first—JSON, auth, encoding, and more.

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Select a developer utility category to view specialized tools.

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How we build

Built for real developer workflows

One place for everyday utilities, package research, and client-side processing.

Private by default

Sensitive payloads stay on your device. No account required to format JSON or decode a JWT.

Instant feedback

Tools run in the browser with Web Workers and WASM where it matters—no round trip to our servers.

Growing catalog

Live tools ship continuously; the full catalog tracks what is active today and what is coming next.