Everyday developer utilities in one searchable browser workspace: format JSON, compare payloads, test regex, generate QR codes, keep notes, and sketch on a whiteboard.
Try the hosted toolkit · Run locally · Questions and feedback
Made by Chandan Singh · GitHub
Actual interface from an isolated local production-mode server. The short URL-encoding walkthrough uses invented example text and two captured states, with condensed timing.
| Need | Tool | Example |
|---|---|---|
| Read a response | JSON Tools | Format {"name":"demo","ready":true} and explore its tree |
| Compare requests | Compare Tools | Compare two sanitized JSON payloads or cURL commands |
| Escape a query value | URL Encoder / Decoder | Encode hello world to hello%20world |
| Share text visually | QR Code Generator | Encode https://example.com and download a PNG |
| Work through an idea | Editor Pad / Brainstorm | Write a note or draw on the whiteboard |
Also available: Base64, calculator (including Weight Price), JWT generation, passwords, regex, short URL expansion, timestamps, and UUIDs. See the full tool reference.
Requirements: Node.js 26 and pnpm 10+, following the contribution guide.
git clone https://github.com/chandanankush/dev-tools.git
cd dev-tools
pnpm install --frozen-lockfile
pnpm devOpen http://localhost:3000. For a production build, run pnpm build and then pnpm start. For self-hosting with Docker, see deployment.
- Most utility processing takes place in your browser. Short URL Expander sends the submitted URL to the server, which makes network requests to resolve redirects. Read the privacy policy before using sensitive data.
- The footer visitor count is a single number stored on the server. It counts unique browsers using a flag in your browser storage and keeps no IP address or visit history.
- Saved notes, calculator history, theme, and drawing preferences use browser storage. Storage limits apply; clearing site data can remove saved work. Export notes you need to keep.
- No universal offline guarantee: initial page loading, external resources, and the URL expander may need network access. Clipboard and download behavior depend on browser permissions and capabilities.
- Password/JWT utilities are tools, not a credential vault or token-security audit. Use invented values in public examples and reports.
- The hosted site may lag behind
main. A release or passing test run does not establish compatibility with every device.
Ask questions in Discussions, starting with the welcome thread. Report reproducible bugs with the tool URL, browser/OS, and sanitized input.
Read CONTRIBUTING and browse good first issues or browser-testing requests. Runtime contributions follow the repository's development → main PR workflow.
This is a public repository, so keep secrets, private hostnames and personal data out of issues, PRs and examples. Report security vulnerabilities privately — see SECURITY.md.
Developer references: architecture, scripts and implementation, test cases, and agent rules.
MIT.