API Rate Limit Simulator

See how rate limiting behaves

Rate limiting controls how many requests a client may make, and the token bucket algorithm is the common approach, but its behaviour under bursts is not obvious. This tool simulates request bursts to visualise the token bucket algorithm, so you can see how a limiter responds.

Why visualising helps understanding

The token bucket algorithm allows bursts up to a bucket size while enforcing a steady average rate, refilling tokens over time, and this interplay is hard to reason about in the abstract. Simulating bursts and watching tokens deplete and refill makes it concrete: you see when requests are allowed, when they are rejected, and how the burst allowance and refill rate shape the behaviour. Understanding this is essential for setting sensible limits and for building or debugging a rate limiter, where the wrong parameters either throttle legitimate traffic or fail to stop abuse.

Understand the algorithm

It runs entirely in your browser, so nothing you paste is uploaded and the result is yours to copy straight into a project. Because it works client-side, you can use it on private code and data without anything leaving your machine.

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