# date-fns v4.1.0

- Product: date-fns (https://whatsnew.fyi/product/date-fns)
- Vendor: date-fns
- Date: 2024-09-17
- Version: v4.1.0
- Original notes: https://github.com/date-fns/date-fns/releases/tag/v4.1.0
- Permalink: https://whatsnew.fyi/product/date-fns/releases/v4.1.0

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This release adds time zone support to format functions (that I somehow missed when working on the feature) and fixes a few bugs.

Make sure also upgrade `TZDate` to v1.0.2 as it [includes a bunch of critical bug fixes](https://github.com/date-fns/tz/blob/main/CHANGELOG.md#v102---2024-09-14).

###### Fixed

- Fixed internal `constructFrom` throwing an exception on `null` arguments. While `null` isn't allowed, the functions should rather return `Invalid Date` or `NaN` in such cases. See [#3885](https://github.com/date-fns/date-fns/issues/3885).

###### Added

- Added missing time zone support to `format`, `formatISO`, `formatISO9075`, `formatRelative` and `formatRFC3339`. See [#3886](https://github.com/date-fns/date-fns/issues/3886).