Ajv vs Yup

Side-by-side NPM package comparison

ajv

Extremely Popular

Version 8.18.0

85
Excellent

Another JSON Schema Validator

Weekly Downloads
241.0M
39%
Bundle (gzip)
31.9 KB
Updated
Vulns
0

Health Score Breakdown

Maintenance
100
Popularity
100
Quality
50
Security
100
Stability
70

yup

Very Popular

Version 1.7.1

73
Good

Dead simple Object schema validation

Weekly Downloads
9.8M
28%
Bundle (gzip)
79.2 KB
Updated
Vulns
0

Health Score Breakdown

Maintenance
60
Popularity
100
Quality
50
Security
100
Stability
70

Choosing between Ajv and Yup? 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.

Downloads & Popularity

Ajv leads with 241.0M weekly downloads — roughly 24.6x more. Yup has 9.8M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.

Bundle Size

Ajv has the smallest gzipped bundle at 31.9 KB. Yup comes in at 79.2 KB. A smaller bundle size means faster page loads, which improves user experience and Core Web Vitals scores.

Health Score Comparison

Ajv has an overall health score of 85/100 (very good), with strong maintenance, security, popularity scores. Yup has an overall health score of 73/100 (good), with strong security, popularity scores. Health scores are calculated from maintenance activity, code quality, security posture, popularity, and stability metrics.

When to Choose Each

Choose Ajv if you value massive community and ecosystem, actively maintained, strong security track record. Choose Yup if you value large community support, strong security track record.

Our Verdict

Both Ajv and Yup are solid choices for JavaScript development. Ajv 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.

Frequently Asked Questions

Is ajv better than yup?
It depends on your needs. Ajv has a health score of 85/100 while Yup scores 73/100. Ajv has more weekly downloads (241.0M), suggesting broader adoption. Consider your specific requirements — bundle size, community support, and feature set — to decide which is the better fit.
Which has a smaller bundle size, ajv or yup?
Ajv has the smaller gzipped bundle at 31.9 KB. A smaller bundle means faster load times for your users, which can positively impact SEO and user experience.
How many developers use ajv vs yup?
Based on npm download statistics, Ajv has approximately 241.0M weekly downloads and Yup has approximately 9.8M weekly downloads. These numbers reflect package installations, not unique developers, but they indicate relative adoption levels.
Which is better maintained, ajv or yup?
Ajv currently has the higher overall health score at 85/100. Ajv has a maintenance score of 100/100 and Yup scores 60/100 on maintenance.

Related Comparisons