Version 8.18.0
0
79
GoodAnother JSON Schema Validator
- Weekly Downloads
- 251.1M
↑22%
- Bundle (gzip)
- 31.9 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
80
Popularity
100
Quality
50
Security
100
Stability
70
Ajv vs Zod
Side-by-side NPM package comparison
Quick Verdict
Smallest Bundle
Ajv
31.9 KB gzipped
Most Popular
Ajv
251.1M weekly downloads
Best Maintained
Ajv
80/100 maintenance score
Highest Quality
Zod
80/100 quality score
Overall Pick
Ajv
Best all-around based on popularity, size, maintenance & quality
Version 4.3.6
0
86
ExcellentTypeScript-first schema declaration and validation library with static type inference
- Weekly Downloads
- 139.2M
↑38%
- Bundle (gzip)
- 57.1 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
80
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 251.1M weekly downloads — roughly 1.8x more. Zod has 139.2M 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. Zod comes in at 57.1 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 86/100 (very good), 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, strong security track record.
Our Verdict
Both Ajv and Zod are solid choices for JavaScript development. Zod has the edge in overall health score (86/100), 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 86/100. Ajv has more weekly downloads (251.1M), 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?
- 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 zod?
- Based on npm download statistics, Ajv has approximately 251.1M weekly downloads and Zod has approximately 139.2M 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 86/100. Ajv has a maintenance score of 80/100 and Zod scores 80/100 on maintenance.
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