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Comparison guide

Ajv vs Yup

Side-by-side NPM package comparison

Quick Verdict

Smallest Bundle

Yup

13.1 KB gzipped

Most Popular

Ajv

391.1M weekly downloads

Best Maintained

Ajv

60/100 maintenance score

Highest Quality

Ajv

50/100 quality score

Overall Pick

Ajv

Best all-around based on popularity, size, maintenance & quality

  1. ajv

    Another JSON Schema Validator

    391.1M weekly downloads · 32.0 KB gzip · Health 73/100

    0
  2. yup

    Dead simple Object schema validation

    12.1M weekly downloads · 13.1 KB gzip · Health 61/100

    0

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 391.1M weekly downloads — roughly 32.4x more. Yup has 12.1M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.

Bundle Size

Yup has the smallest gzipped bundle at 13.1 KB. Ajv comes in at 32.0 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 73/100 (good), with strong security, popularity scores. Yup has an overall health score of 61/100 (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, strong security track record. Choose Yup if you value massive community and ecosystem, strong security track record.

Our Verdict

Both Ajv and Yup are solid choices for JavaScript development. Ajv has the edge in overall health score (73/100), 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 73/100 while Yup scores 61/100. Ajv has more recorded weekly downloads (391.1M). 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?
Yup has the smaller gzipped bundle at 13.1 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?
Ajv has more recorded weekly downloads (391.1M). Download counts reflect package installations, not unique developers.
Which is better maintained, ajv or yup?
Ajv has a maintenance score of 60/100. Ajv scores 60/100 and Yup scores 20/100 on maintenance.

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One PDF: the best package for every category (ORMs, bundlers, auth, testing, state management). Used by 500+ devs. Free, updated monthly.