[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Time](https://evolu.dev/docs/api-reference/common/Time) › performanceDurationBetween

```ts
function performanceDurationBetween(
  start: PerformanceTime,
  end: PerformanceTime,
): PerformanceDuration;
```

Defined in: [packages/common/src/Time.ts:445](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Time.ts#L445)

Returns the elapsed fractional milliseconds between two performance times.

Throws if `end` precedes `start`.