Free Tool

Load Model Calculator

Turn throughput targets and response time baselines into virtual user counts and load profiles. Outputs ready-to-paste config for JMeter, k6, and Gatling.

Uses Little's Law: VUs = Throughput (req/s) × (Response Time (s) + Think Time (s)). Models a sustained load at a constant arrival rate.

Target throughput (req/s)

e.g. 10 = 10 requests every second

Average response time (ms)

Think time (s)

Pause between requests per virtual user. Use 0 for open-model tools.

Ramp-up duration (minutes)

Added before the execution window. Use 0 for an immediate full load.

Execution duration (minutes)

Steady-state window only — ramp-up is additional.

Ready to run the test?

Now you have the numbers — get the scripts.

Perf Lab gives you production-ready JMeter, k6, and Gatling templates across 17+ protocols, ready to drop your VU counts into.

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