# What changed in dateformat

> 4 changes in dateformat 5 from its official release notes, upgrade guides and advisories. Each one cited. Sources checked 2026-10-18. HTML: https://unstale.sh/npm/dateformat/

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

## dateformat 5

### Fixes and other changes

- N now uses the UTC weekday when the mask uses UTC: or GMT:. (5.0.4) — [release notes](https://github.com/felixge/node-dateformat/releases/tag/v5.0.4)
- W now uses the UTC week when the mask uses UTC: or GMT:. (5.0.4) — [release notes](https://github.com/felixge/node-dateformat/releases/tag/v5.0.4)
- WW now uses the UTC week when the mask uses UTC: or GMT:. (5.0.4) — [release notes](https://github.com/felixge/node-dateformat/releases/tag/v5.0.4)
- Fixed yy returning incorrect digits for years outside 1000 to 9999, including negative years. (5.0.4) — [release notes](https://github.com/felixge/node-dateformat/releases/tag/v5.0.4)