I Built a REST API Tester That Runs Entirely in Your Browser

Every API tester tool wants you to install an app, create an account, or pay monthly. I built one that needs none of that.

What it does

API Tester Pro is a single HTML file. Open it in any browser and you have a full REST client:

• GET, POST, PUT, DELETE, PATCH support
• Custom headers (JSON format)
• Request body editor
• Response viewer with status codes + timing
• Zero dependencies, zero uploads

Why browser-based matters

• No install — works on any device with a browser
• No CORS issues — requests go directly from your browser
• No data leakage — nothing leaves your machine
• Instant — no loading screens, no updates

Try it free

The free version handles basic requests. No limits, no trial period.

🔗 API Tester — Free Version

Go PRO for $29

The PRO license unlocks collections, request history, environment variables, auth tokens, and export to cURL/code. One-time payment, lifetime access.

🛍️ Get PRO on Gumroad

I also built 6 Python CLI tools and 13 other browser tools — all at pyfile-toolkit.github.io.