About Day.js
2KB immutable date time library alternative to Moment.js with the same modern API
How many people use Day.js
GitHub · npm
#5 of 198 JavaScript libraries we have counts for (of 232) · bars are GitHub stars across these neighbours; the category leader is Axios at 109k · as of September 7, 2026
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Day.js#5 of 198 JavaScript libraries
Htmx#4 of 198 JavaScript libraries
The two numbers disagree - one leads on stars, the other on installs. Stars measure attention, downloads measure use.
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We measure the detected version against Day.js's release history and grade the surrounding stack with a Lighthouse-grade quality audit. Weak or outdated links weigh more - one risky dependency can pull the whole score down.
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