---
title: "What is burst capacity?"
description: "Burst capacity is how many environments a provider actually delivers when many are requested at once, which is often very different from its advertised latency for one."
url: "https://www.promigence.ai/glossary/burst-capacity"
site: "Promigence"
---

# What is burst capacity?

Burst capacity is how many environments a provider actually delivers when many are requested at once, which is often very different from its advertised latency for one.

The gap is measurable, and it moves. In an independent test requesting 100 concurrent sandboxes, one provider went from serving 12 to serving all 100 within two weeks. Both runs are real, which is the point: one good day tells you nothing about the next one.

For batch work this is the reliability number that matters. A fan-out that half-completes invalidates an evaluation rather than degrading it, because the environments that did not start are not a random sample.

## Related
- https://www.promigence.ai/glossary/validity-report