Directory
date-fns + Day.js
Date formatting
FreeLibraries & build toolingdate-fns.org
What it is
The two live replacements for the deprecated Moment.js. date-fns (v4) is a tree-shakeable set of pure functions with first-class time-zone support. Day.js is a 2KB immutable wrapper with a Moment-compatible API and optional plugins.
Why it earns a slot
Relative timestamps, date maths and time zones are where hand-written code quietly breaks across DST and locales. Pick date-fns for tree-shaking, Day.js for the smallest bundle or a Moment port.
Know before you commit
Never install Moment.js — it is in maintenance mode and ships huge locale files. The native
Temporal API is arriving but is not yet safe to rely on everywhere.Getting started
npm install date-fns
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