Overview
Web3.js, Ethers.js, and Viem are the three most popular JavaScript libraries for interacting with Ethereum. This guide compares their features, performance, and developer experience.
Feature Comparison
| Feature | Web3.js | Ethers.js | Viem |
|---|---|---|---|
| Bundle Size | ~500KB | ~150KB | ~80KB |
| TypeScript | Partial | Yes | Native |
| License | LGPL-3.0 | MIT | MIT |
| Maintenance | Active | Active | Very Active |
| Documentation | Good | Excellent | Good |
Performance
| Metric | Web3.js | Ethers.js | Viem |
|---|---|---|---|
| Bundle Size | Largest | Medium | Smallest |
| Tree Shake | Limited | Good | Excellent |
| Parse Speed | Medium | Fast | Fastest |
Developer Experience
Web3.js
- Oldest and most battle-tested
- Large community and resources
- Can feel dated compared to modern alternatives
Ethers.js
- Best documentation
- Clean, intuitive API
- Great for beginners
Viem
- Modern, type-safe by default
- Best performance
- Used by Wagmi and RainbowKit
Verdict
- Best for Beginners - Ethers.js
- Best Performance - Viem
- Best for Legacy Projects - Web3.js
- Best for New Projects - Viem