Toolbit

Developer Workspace for JSON, JWT, API and Data Tools

Toolbit is a local-first developer workspace with 42 offline tools — JSON formatter, JWT decoder, Base64 encoder, regex tester, SQL formatter, YAML formatter, UUID generator, hash generator, cron parser, CSV to JSON converter and more. Everything runs in your browser: no uploads, no tracking, no sign-up.

Popular tools

JSON, YAML & Format Tools

Beautify, minify, and validate the structured formats you read all day.

Encoding & Token Tools

Encode, decode, and inspect Base64, URLs, JWTs, certificates, and wire formats.

Generators

Produce identifiers, hashes, passwords, QR codes, and realistic test data.

Converters

Move data between formats, units, colours, timestamps, and cases.

Inspect & Compare

Test regular expressions, diff text, read git patches, and decode schedules.

API & Command Builders

Compose HTTP requests, WebSocket sessions, cron entries, and Docker commands.

Text & Document Tools

Clean up text, preview Markdown, work with PDFs, and do date maths.

Why Toolbit?

Runs locally

Every transformation happens in your browser with standard Web APIs. There is no backend to send your data to.

No uploads

Files you drop in are read from disk and processed in the tab. They are never transmitted, so confidential documents stay confidential.

Works offline

Install it once and the whole toolbox keeps working on a plane, on a locked-down network, or on an air-gapped machine.

40+ developer utilities

Formatters, encoders, generators, converters, and inspectors for the tasks that interrupt real work.

Workspace mode

Open several tools as tabs, pipe output from one into the next, and keep your working set in view.

Keyboard shortcuts

A command palette and shortcuts for everything, so you never reach for the mouse mid-thought.

Frequently asked questions

Does Toolbit upload my files?
No. Every Toolbit tool runs entirely in your browser using standard Web APIs. Your input is never uploaded, logged, or sent to a third party — you can open the network tab and watch it stay quiet.
Can I use Toolbit offline?
Yes. Toolbit installs as a PWA and ships as a desktop app for macOS, Windows, and Linux, so the whole toolbox keeps working on a plane, behind a corporate firewall, or on an air-gapped machine.
Is Toolbit free?
Yes. Every tool is free to use, there is no sign-up, no account, no paid tier, and no advertising. The project is open source under the MIT licence.
Does Toolbit support JSON?
Yes. Toolbit includes a JSON formatter, a JSON Schema validator, a collapsible tree viewer, a CSV to JSON converter, and YAML and XML converters that read and write JSON.
Does Toolbit track me?
No. There is no analytics script, no cookie banner, and no third-party request. The app makes no network calls once it has loaded, apart from requests you explicitly send with the API and WebSocket tools.
Is there a desktop version?
Yes. Toolbit ships as a native desktop app for macOS, Windows, and Linux, and installs as a PWA from the browser for offline use.

From the blog