A REST API Tester That Runs Entirely in the Browser — No Server, No Logs

javascript dev.to

Postman is great, but sometimes you just want to fire one request from a machine you don't control — a shared laptop, a kiosk, a friend's phone — without installing anything or leaving request history anywhere.

So we built a REST API Tester as a plain web page:

  • Method + URL + headers + JSON body, like a pocket cURL
  • Shows status, latency, response headers and pretty-printed body
  • Zero backend: the request goes straight from your browser's fetch() to the target. There is no proxy to log it, because there is no proxy.

The one real constraint: CORS

A browser tab can only hit endpoints that send Access-Control-Allow-Origin. That's not a bug to hack around — it's the security model working as designed. We lean into it: the tool is perfect for public CORS-enabled APIs (GitHub, open data, your own services during dev), and it prints a clear explanation when a target refuses cross-origin calls.

Why this matters for indie builders

  • No request logs exist — a genuine privacy feature you can truthfully advertise.
  • Hosting cost ≈ zero — static HTML + JS, CDN-cached.
  • It's part of a larger suite of 385 local-only tools (sitemap: https://toolfyra.com/sitemap.xml).

Source-free, signup-free, free. Try it: https://toolfyra.com/rest-api-tester.html

Disclosure: I'm the maintainer. PRs and roast welcome.

Source: dev.to

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