Version 5.8.4
0
85
ExcellentFast and low overhead web framework, for Node.js
- Weekly Downloads
- 5.6M
↑21%
- Bundle (gzip)
- 815.4 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
100
Popularity
100
Quality
50
Security
100
Stability
70
Fastify vs Koa
Side-by-side NPM package comparison
Quick Verdict
Smallest Bundle
Koa
19.0 KB gzipped
Most Popular
Koa
6.3M weekly downloads
Best Maintained
Fastify
100/100 maintenance score
Highest Quality
Fastify
50/100 quality score
Overall Pick
Koa
Best all-around based on popularity, size, maintenance & quality
Version 3.2.0
0
85
ExcellentKoa web app framework
- Weekly Downloads
- 6.3M
↑15%
- Bundle (gzip)
- 19.0 KB
- Updated
- Vulns
- 0
Health Score Breakdown
Maintenance
100
Popularity
100
Quality
50
Security
100
Stability
70
Choosing between Fastify and Koa? 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
Koa leads with 6.3M weekly downloads — roughly 1.1x more. Fastify has 5.6M weekly downloads. Higher download counts generally indicate broader community adoption and a larger ecosystem of tutorials, plugins, and support.
Bundle Size
Koa has the smallest gzipped bundle at 19.0 KB. Fastify comes in at 815.4 KB. A smaller bundle size means faster page loads, which improves user experience and Core Web Vitals scores.
Health Score Comparison
Fastify has an overall health score of 85/100 (very good), with strong maintenance, security, popularity scores. Koa 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 Fastify if you value large community support, actively maintained, strong security track record. Choose Koa if you value large community support, actively maintained, strong security track record.
Our Verdict
Both Fastify and Koa are solid choices for JavaScript development. Fastify 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 fastify better than koa?
- It depends on your needs. Fastify has a health score of 85/100 while Koa scores 85/100. Koa has more weekly downloads (6.3M), 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, fastify or koa?
- Koa has the smaller gzipped bundle at 19.0 KB. A smaller bundle means faster load times for your users, which can positively impact SEO and user experience.
- How many developers use fastify vs koa?
- Based on npm download statistics, Fastify has approximately 5.6M weekly downloads and Koa has approximately 6.3M weekly downloads. These numbers reflect package installations, not unique developers, but they indicate relative adoption levels.
- Which is better maintained, fastify or koa?
- Fastify currently has the higher overall health score at 85/100. Fastify has a maintenance score of 100/100 and Koa scores 100/100 on maintenance.
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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.