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Comparison guide
Ajv vs Joi
Side-by-side NPM package comparison
Quick Verdict
Smallest Bundle
Ajv
32.0 KB gzipped
Most Popular
Ajv
474.0M weekly downloads
Best Maintained
Joi
100/100 maintenance score
Highest Quality
Ajv
50/100 quality score
Overall Pick
Ajv
Best all-around based on popularity, size, maintenance & quality
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Choosing between Ajv and Joi? 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 474.0M weekly downloads — roughly 15.2x more. Joi has 31.1M 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 32.0 KB. Joi comes in at 51.2 KB. A smaller bundle size means faster page loads, which improves user experience and Core Web Vitals scores.
Health Score Comparison
Joi has an overall health score of 85/100 (very good), with strong maintenance, security, popularity scores. Ajv 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, strong security track record. Choose Joi if you value massive community and ecosystem, actively maintained, strong security track record.
Our Verdict
Both Ajv and Joi are solid choices for JavaScript development. Joi 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 joi?
- It depends on your needs. Ajv has a health score of 73/100 while Joi scores 85/100. Ajv has more recorded weekly downloads (474.0M). 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 joi?
- Ajv has the smaller gzipped bundle at 32.0 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 joi?
- Ajv has more recorded weekly downloads (474.0M). Download counts reflect package installations, not unique developers.
- Which is better maintained, ajv or joi?
- Joi has a maintenance score of 100/100. Ajv scores 60/100 and Joi scores 100/100 on maintenance.
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