# What changed in fast-equals

> 9 changes in fast-equals 5 to 6 from its official release notes, upgrade guides and advisories: 1 breaking. Each one cited. Sources checked 2026-10-21. HTML: https://unstale.sh/npm/fast-equals/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## fast-equals 6

### Breaking changes

- Strict modes now compare Date own properties. (6.2.0) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.0)

### Performance

- Map comparisons are faster. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)
- Set comparisons are faster. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)
- Strict TypedArray comparisons are faster. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)

### Fixes and other changes

- AggregateError contents are compared using the configured equality. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)
- Error comparisons are more correct. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)
- Object comparison enumerability is symmetric. (6.2.1) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v6.2.1)

## fast-equals 5

### Fixes and other changes

- Fixes error comparison behavior. (5.4.5) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v5.4.5)
- Fixes object comparison behavior. (5.4.5) — [release notes](https://github.com/planttheidea/fast-equals/releases/tag/v5.4.5)