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Comparison guide
Joi vs Zod
Side-by-side NPM package comparison
Quick Verdict
Smallest Bundle
Joi
51.2 KB gzipped
Most Popular
Zod
334.4M weekly downloads
Best Maintained
Joi
100/100 maintenance score
Highest Quality
Zod
80/100 quality score
Overall Pick
Zod
Best all-around based on popularity, size, maintenance & quality
zod
TypeScript-first schema declaration and validation library with static type inference
334.4M weekly downloads · 86.5 KB gzip · Health 92/100
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Choosing between Joi and Zod? 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
Zod leads with 334.4M weekly downloads — roughly 13.0x more. Joi has 25.7M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.
Bundle Size
Joi has the smallest gzipped bundle at 51.2 KB. Zod comes in at 86.5 KB. A smaller bundle size means faster page loads, which improves user experience and Core Web Vitals scores.
Health Score Comparison
Zod has an overall health score of 92/100 (excellent), with strong maintenance, quality, security, popularity scores. Joi 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.
When to Choose Each
Choose Joi if you value massive community and ecosystem, actively maintained, strong security track record. Choose Zod if you value massive community and ecosystem, actively maintained, strong security track record.
Our Verdict
Both Joi and Zod are solid choices for JavaScript development. Zod has the edge in overall health score (92/100), 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 joi better than zod?
- It depends on your needs. Joi has a health score of 85/100 while Zod scores 92/100. Zod has more recorded weekly downloads (334.4M). Consider your specific requirements — bundle size, community support, and feature set — to decide which is the better fit.
- Which has a smaller bundle size, joi or zod?
- Joi has the smaller gzipped bundle at 51.2 KB. A smaller bundle means faster load times for your users, which can positively impact SEO and user experience.
- How many developers use joi vs zod?
- Zod has more recorded weekly downloads (334.4M). Download counts reflect package installations, not unique developers.
- Which is better maintained, joi or zod?
- Joi has a maintenance score of 100/100. Joi scores 100/100 and Zod scores 100/100 on maintenance.
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