Latency Benchmark
Benchmark and visualize API latency with percentile statistics
Configuration
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What is Latency Benchmarking?
Latency benchmarking measures how long API calls take to complete. For LLM applications, understanding latency distribution helps you set realistic timeouts, improve user experience, and identify performance issues.
This simulator demonstrates latency profiling concepts. Configure delay ranges to simulate different API behaviors and see how percentiles reveal the full latency picture.
Understanding Percentiles
P50 (Median)
Half of requests complete faster than this. Good for typical user experience.
P95 / P99 (Tail)
Worst-case latencies. Set timeouts based on these to avoid user frustration.
Typical LLM API Latencies
| API Type | Typical P50 | Typical P95 |
|---|---|---|
| GPT-4 (short) | 500-1000ms | 2-5s |
| GPT-3.5 | 200-500ms | 1-2s |
| Embeddings | 50-200ms | 300-500ms |
FAQ
Does this call real APIs?
No. This simulates latency with random delays. Use for learning percentile concepts before real benchmarking.
What timeout should I set?
Use P99 or max latency from real benchmarks. Add buffer for network variance. Typical: 30-60s for LLMs.