Modern JavaScript date utility library
- Weekly Downloads
- 87.0M
- Bundle (gzip)
- 17.1 KB
- Updated
- Vulns
- 0
Comparison guide
Side-by-side NPM package comparison

Smallest Bundle
Dayjs
3.0 KB gzipped
Most Popular
Date-fns
87.0M weekly downloads
Best Maintained
Date-fns
100/100 maintenance score
Highest Quality
Date-fns
50/100 quality score
Overall Pick
Dayjs
Best all-around based on popularity, size, maintenance & quality
Modern JavaScript date utility library
2KB immutable date time library alternative to Moment.js with the same modern API
Choosing between Date-fns and Dayjs? Here's a data-driven comparison based on real npm data — downloads, bundle size, health scores, and more — to help you decide which package fits your project best.
Date-fns leads with 87.0M weekly downloads — roughly 1.6x more. Dayjs has 54.0M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.
Dayjs has the smallest gzipped bundle at 3.0 KB. Date-fns comes in at 17.1 KB. A smaller bundle size means faster page loads, which improves user experience and Core Web Vitals scores.
Date-fns has an overall health score of 85/100 (very good), with strong maintenance, security, popularity scores. Dayjs has an overall health score of 85/100 (very good), with strong maintenance, security, popularity scores. Health scores are calculated from maintenance activity, code quality, security posture, popularity, and stability metrics.
Choose Date-fns if you value massive community and ecosystem, actively maintained, strong security track record. Choose Dayjs if you value massive community and ecosystem, minimal bundle footprint, actively maintained, strong security track record.
Both Date-fns and Dayjs are solid choices for JavaScript development. Date-fns has the edge in overall health score (85/100), while each package brings unique strengths to the table. Evaluate them based on your project's priorities — whether that's community size, bundle efficiency, or maintenance activity — and choose the one that aligns best with your requirements.
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