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Free API Retry Logic Tester
Simulate API failures (429, 503, timeouts) and verify your retry logic handles them correctly. Test exponential backoff, jitter, and circuit breaker patterns.
What We Check
- 1Enter API endpoint — Enter your API endpoint URL and configure failure simulation.
- 2Choose failure type — Choose failure type: 429 rate limit, 503 service unavailable, connection timeout, or random errors.
- 3Failure simulation — PingSLA sends requests and simulates the configured failure responses.
- 4Retry behaviour observed — Your endpoint's retry behaviour observed and recorded.
- 5Retry interval measured — Retry interval measured: linear, exponential, or exponential with jitter.
- 6Retry totals recorded — Total retry attempts and final success/failure recorded.
- 7Implementation report — Report shows whether retry logic is correctly implemented.
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Frequently Asked Questions
- What is exponential backoff and why does it matter?
- Exponential backoff is a retry strategy where each successive retry waits twice as long as the previous one. Without it, retrying too aggressively under a 429 rate limit makes the problem worse. The retry tester verifies your implementation waits the correct intervals.
- How do I test circuit breaker patterns?
- Configure the tester to return failures continuously for a set duration, then observe whether your circuit breaker opens (stops sending requests) after the configured failure threshold. A working circuit breaker prevents cascading failures under load.