API Tester
Test HTTP REST API endpoints directly from your browser. Send custom HTTP requests, query parameters, header credentials, and raw JSON payloads. Bypasses browser CORS policy limitations.
CORS Helper Extension: DISCONNECTEDStandard fetch active. Requests to non-CORS APIs will fail. Download helper zip to bypass.
Extension ID:
Response Payload
Frequently Asked Questions
How can I bypass browser CORS restrictions?
By installing our privileged companion Chrome Extension (available as a ZIP download directly from the tool), requests are relayed through a sandboxed Service Worker that ignores standard Same-Origin policy limits.
Is my API token or header data stored anywhere?
No. All requests are sent directly from your browser (or relayed client-side via the companion extension service worker) to the destination API server. No data is stored or logged.
Does this tool support authorization headers?
Yes. You can add custom headers like 'Authorization: Bearer <token>' or 'API-Key' in the Headers configuration tab.