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MondayKit

2 Free Developer tools

Developer tools

MondayKit developer tools cover small jobs that come up every day. Format, validate and minify JSON with exact error positions and a collapsible tree, generate QR codes for URLs, Wi-Fi networks and vCards in PNG or SVG, encode images as Base64 data URIs, and compare text or code with a diff checker. Because everything runs locally in your browser – heavy parsing happens in a Web Worker – you can safely paste API responses, tokens and configuration files without sending them to a third-party server.

  • 100% FreeNo hidden charges
  • Privacy FirstFiles stay in your browser
  • No SignupNo account or email needed

All developer tools

JSON formatterPopularFormat, validate, minify and explore JSON.QR code generatorPopularCreate QR codes for URLs, Wi-Fi, vCards and more – PNG or SVG.

More tools you may need

Image to Base64Encode an image as a Base64 data URI with copy-ready snippets.Text diff checkerCompare two texts and highlight additions and deletions.

Frequently asked questions

Is it safe to paste private JSON?

Yes. JSON is parsed in your browser and never sent to a server.

Do generated QR codes expire?

No. They are static codes that work forever.

Can I use the output commercially?

Yes. QR codes and formatted output are yours to use.

Is there an API?

Not at launch; all tools are browser-only.

Need something else?

Search all free MondayKit tools – they all run in your browser.