API endpoint tester
Send one request to a public API endpoint from our server and see the HTTP status code it returns, how long it took and whether it counts as a success. It's a quick way to confirm an endpoint is up and reachable from the internet.
What this tool checks
Status code
The HTTP status the endpoint returns, after following up to 5 redirects.
Response time
The full round trip from our server in milliseconds, including DNS lookup, connection set-up and any redirects.
Success or failure
A request succeeds when the final status is below 400. Timeouts (after 15 seconds), connection failures and blocked addresses are shown as errors.
How the check works
Our server sends the request with the method, headers and body you enter. The body is sent exactly as typed, so add a Content-Type header if the API expects JSON or form data. The response body is not shown or kept.
For safety, only public internet addresses can be tested. Addresses on private networks — localhost, 10.x.x.x, 192.168.x.x, cloud metadata services and similar — are blocked, and every redirect is checked the same way.
You need a free account to use the tester, and requests are rate-limited per network. We save the endpoint URL, method, status code, response time and any error with your account; headers and body are not saved.
Common problems we find
401 or 403
The endpoint needs authentication, or the key or token sent isn't allowed.
404 Not Found
A wrong path, a missing version prefix such as /v1, or a trailing slash the API doesn't expect.
405 Method Not Allowed
The endpoint exists but doesn't accept this method — for example POST to a read-only resource.
400 or 415
The body is malformed, or the Content-Type header is missing or wrong.
429 Too Many Requests
The API's own rate limit was reached.
5xx errors and timeouts
The API is down, overloaded, or taking longer than 15 seconds to answer.
How to fix them
Send the right credentials
Add an Authorization header in the format the API documents, for example Authorization: Bearer followed by your token. Use a test key rather than a production secret.
Check the path against the documentation
Compare the URL with the API reference, including version prefixes, trailing slashes and query parameters.
Match the body and Content-Type
For JSON, send valid JSON and the header Content-Type: application/json.
Investigate slow responses
Response times of several seconds usually point to slow database queries, cold starts on serverless hosting, or a server far from our location.
Frequently asked questions
Why do I need an account?
The request is sent from our server to an address you choose. Requiring a free account and rate-limiting requests prevents the tester from being used to send anonymous traffic to other people's servers.
Can I test localhost or an internal API?
No. Private and internal addresses are blocked on purpose, so the tester can't be used to reach our own internal network. To test a local API, use a tool that runs on your own computer.
Why can't I see the response body?
The tester reports whether the endpoint is reachable and how quickly it answers. It doesn't display or keep the response content.
Are my API keys stored?
Headers and the request body are sent to the endpoint but not saved. The endpoint URL is saved with the result, so don't put secrets in the URL's query string.
Why is the response time different from what I see locally?
It's measured from our server, not your computer, so distance, routing and connection set-up differ. It's best for comparing an endpoint with itself over time.
Can I use it for load testing?
No. It sends a single request each time and is rate-limited. Use a dedicated load-testing tool, only against servers you're allowed to test.
Related free tools
Rather have someone fix it for you?
These checks are free and so are the guides. If you'd prefer a person to make the changes, our team offers paid help.