API Health Checker

Server assisted API Testing

Paste up to 10 public URLs to run a health sweep: each is checked for status code, response time and optional expected body text, with a colour-coded summary.

Privacy: This tool sends the request through the Mutqan backend relay to reach the target. Only the target URL, headers and body you enter are transmitted, and nothing is stored.

What is API testing?

API testing checks a service through its interface rather than its screens: send a request with a chosen method, headers and body, then verify the status code, the response headers, the body's structure and values, and the time it took. Because it runs below the UI, it is faster, more stable and catches integration defects earlier — which is why regression suites are built API-first.

Read the guide: What is API Testing? How to Test a REST API

How to use API Health Checker

  1. Paste one URL per line (public health, readiness or version endpoints).
  2. Optionally set the text the body must contain and the slow threshold.
  3. Run the check and review the summary, then the per-endpoint table.
  4. Download the CSV or copy the Markdown report.

API Health Checker features

  • Check up to 10 health endpoints in one sweep through the relay
  • Status, latency, size and optional expected body text per endpoint
  • UP / SLOW / FAIL / DOWN verdict per endpoint (FAIL: not 2xx/3xx or expected text missing; DOWN: unreachable) with a configurable slow threshold
  • Summary stats and a Markdown report ready to paste into a status update
  • CSV export of the result table

API Health Checker example

Sweep three services

Input:

https://httpbin.org/status/200
https://httpbin.org/delay/1
https://httpbin.org/status/503

Output:

Healthy 1 · Slow 1 · Failing 1 · Avg latency 780 ms
UP    https://httpbin.org/status/200   200 OK   190 ms
SLOW  https://httpbin.org/delay/1       200 OK   1.2 s
FAIL  https://httpbin.org/status/503   503 Service Unavailable

Frequently asked questions about API Health Checker

How many URLs can I check?

Up to 10 per sweep. Each URL is fetched through the relay with a short timeout and reported with status, latency and size.

What counts as healthy?

A 2xx/3xx status within the timeout — and, if you set an expected body text, the body must contain it. Responses slower than your threshold are flagged as SLOW.

Can I monitor continuously?

This is an on-demand check; re-run it whenever you need. For scheduled monitoring use a dedicated uptime service.

Why does an endpoint show DOWN although it works in my browser?

The relay reaches only public addresses; internal, VPN-only or localhost services cannot be checked.

Technical notes

The relay checks the URLs concurrently with a short timeout and returns status, time and size per URL; endpoints that cannot be reached carry an error message instead of a status.

References

  • RFC 9110: HTTP SemanticsIETF · 2022The meaning of HTTP methods, header fields, status codes and content negotiation, independent of the wire version.
  • OpenAPI SpecificationOpenAPI InitiativeThe standard for describing REST APIs: paths, operations, parameters, schemas, responses and security schemes.
  • OWASP Cheat Sheet Series: REST SecurityOWASP FoundationSecurity rules for REST APIs: HTTPS, authentication on every request, input validation, safe error responses, rate limiting.