In the same workflow: Retry Simulator and Rate Limit Tester.

429 Detector

Send multiple requests to an endpoint and detect 429 (Too Many Requests). See when the first 429 occurs and how many you get.

Why use 429 Detector?

Some APIs only reveal rate limits under sustained use. This helper sends patterned traffic to detect when responses flip to 429 Too Many Requests so you can tune client backoff and cache hotter paths.

Practical tips

  • Respect vendor acceptable use policies; prefer dedicated sandboxes.
  • Capture Retry-After headers when present to model realistic waits.
  • Compare with Rate Limit Tester for more configurable burst shapes.

Common questions

Is this a DDoS tool?
No. It is for engineering diagnostics at modest volumes on endpoints you control or are authorized to test.
Why never see 429?
Limits may be per API key, IP, or account. Confirm you are exercising the same dimension vendors enforce.

About

Send requests and detect when endpoint returns 429 Too Many Requests. Test rate limit behavior. Free tool.

Related tools

Used together

Next step

After 429-detector, continue with Retry Simulator to validate the next API or webhook layer.