CORS Sandbox
CORS (Cross-Origin Resource Sharing) is the set of response headers that decides whether a browser lets one origin read another's data. Enter a URL, method and headers to see the exact preflight and request the browser would send, and understand why a cross-origin call fails.
What is CORS?
Browsers block JavaScript from reading responses from another origin unless the server opts in with Access-Control-Allow-Origin and friends. For non-simple requests the browser first sends an OPTIONS preflight listing the method and headers, and the server must approve them. CORS is enforced by the browser — curl and servers never see it.
This tool runs entirely in your browser. Your inputs and files are processed locally and are never sent to or stored on Kinetikatech servers.
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