79
GoodAnother JSON Schema Validator
- Weekly Downloads
- 290.5M
↑6%
- Bundle (gzip)
- 302.8 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
80
Popularity
100
Quality
50
Security
100
Stability
70
Comparison guide
Ajv vs Zod
AJV is 7x faster (14M ops/sec) but Zod infers TypeScript types automatically. Compare bundle size, performance, and DX for schema validation in 2026.
Quick Verdict
Smallest Bundle
Zod
60.3 KB gzipped
Most Popular
Ajv
290.5M weekly downloads
Best Maintained
Zod
100/100 maintenance score
Highest Quality
Zod
80/100 quality score
Overall Pick
Zod
Best all-around based on popularity, size, maintenance & quality
92
ExcellentTypeScript-first schema declaration and validation library with static type inference
- Weekly Downloads
- 181.0M
↑13%
- Bundle (gzip)
- 60.3 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
100
Popularity
100
Quality
80
Security
100
Stability
70
Choosing between Ajv 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
Ajv leads with 290.5M weekly downloads — roughly 1.6x more. Zod has 181.0M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.
Bundle Size
Zod has the smallest gzipped bundle at 60.3 KB. Ajv comes in at 302.8 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. Ajv has an overall health score of 79/100 (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 Ajv if you value massive community and ecosystem, strong security track record. Choose Zod if you value massive community and ecosystem, actively maintained, strong security track record.
Our Verdict
Both Ajv 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 ajv better than zod?
- It depends on your needs. Ajv has a health score of 79/100 while Zod scores 92/100. Ajv has more weekly downloads (290.5M), 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 zod?
- Zod has the smaller gzipped bundle at 60.3 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 zod?
- Based on npm download statistics, Ajv has approximately 290.5M weekly downloads and Zod has approximately 181.0M weekly downloads. These numbers reflect package installations, not unique developers, but they indicate relative adoption levels.
- Which is better maintained, ajv or zod?
- Zod currently has the higher overall health score at 92/100. Ajv has a maintenance score of 80/100 and Zod scores 100/100 on maintenance.
Related Comparisons
The 2026 JavaScript Stack Cheatsheet
One PDF: the best package for every category (ORMs, bundlers, auth, testing, state management). Used by 500+ devs. Free, updated monthly.