Add assertions to automatically check the response after each request.
What Is the ZeeSharp API Tester?
The ZeeSharp API Tester is a free, browser-based REST client for sending HTTP requests to any public API endpoint and inspecting the response in detail. It's built for developers, QA engineers and students who need to quickly check an API — verify a status code, debug a CORS issue, inspect response headers, or grab a working code snippet — without installing Postman, Insomnia or any desktop application.
Because requests are routed through a server-side proxy rather than directly from your browser, CORS restrictions don't apply, and you can test third-party APIs that would otherwise be blocked by the browser's same-origin policy. Nothing you send is logged on our servers; request history, saved requests and variables live entirely in your browser's local storage.
Key Features
All HTTP Methods
GET, POST, PUT, PATCH, DELETE, HEAD and OPTIONS — each with full header, auth and body support where applicable.
CORS-Free Proxy
Requests are sent server-side, so cross-origin restrictions that block direct browser calls never apply here.
Built-in Auth
Bearer Token, Basic Auth and API Key headers are generated automatically — no manual header formatting needed.
Params & Variables
Edit query params in a key/value table that syncs with the URL, and reuse values everywhere with {{variables}}.
History & Saved Requests
Your last 30 requests are kept automatically; save important ones with a name to reload them anytime.
JSON Beautify & Validate
One-click JSON formatting with a live valid/invalid badge as you type the request body.
Timing Breakdown
See DNS lookup, TCP connect, TLS handshake, time-to-first-byte and download time for every response.
Code Generation
Instantly copy your request as cURL, JavaScript fetch, Python requests, Node.js axios or PHP cURL.
Test Assertions
Add simple checks — status code, response time, body contains, header exists — and see pass/fail after every send.
How to Test an API Request
- Choose the HTTP method (GET, POST, PUT, PATCH, DELETE, HEAD or OPTIONS).
- Enter the endpoint URL — query parameters can be typed directly in the URL or added in the Params tab.
- Add any required headers, or use the Auth tab for Bearer Token, Basic Auth or an API Key.
- For POST/PUT/PATCH requests, switch to the Body tab, pick a content type and enter the payload — click Beautify to format JSON.
- Click Send and review the status code, timing, headers, cookies and formatted body. Open the Code tab to copy a ready-to-use snippet in your language of choice.
API Tester vs Postman vs Insomnia
| Capability | ZeeSharp API Tester | Postman | Insomnia |
|---|---|---|---|
| Installation required | No — runs in browser | Desktop app / account | Desktop app |
| CORS-free testing | Yes (server proxy) | Yes (desktop app) | Yes (desktop app) |
| Headers, Auth, Body, Params | Yes | Yes | Yes |
| Request history & saved requests | Yes (local) | Yes (cloud) | Yes (local/cloud) |
| Code generation | cURL, JS, Python, Node, PHP | 20+ languages | Several languages |
| Collection runner / CI | Not available | Yes | Yes |
| Mock servers / team workspaces | Not available | Yes (paid tiers) | Limited |
| Best for | Quick checks, sharing a link, no-install environments | Large teams, complex workflows | Power users wanting a lightweight desktop client |