ethers.js

ethers.js is a complete, compact, and powerful JavaScript library for interacting with the Ethereum blockchain and its ecosystem, created and maintained by Richard Moore. It is one of the two most widely-used Ethereum libraries for JavaScript and TypeScript development (alongside viem), powering the frontend of countless decentralized applications (dApps), DeFi protocols, NFT marketplaces, and wallet interfaces. The library is designed with a focus on developer experience, security, and correctness, providing intuitive abstractions over low-level Ethereum JSON-RPC calls. ethers.js v6 (the current major version) introduced significant architectural improvements over v5, including a smaller bundle size (reduced by approximately 40 percent), better TypeScript type inference, a more modular and tree-shakeable design, and improved performance. Core components include: Providers for connecting to Ethereum nodes (JsonRpcProvider, WebSocketProvider, InfuraProvider, AlchemyProvider), Signers for managing private keys and signing transactions (Wallet, JsonRpcSigner), Contracts for type-safe interaction with smart contracts (reading state, sending transactions, listening to events), Utilities for common operations (address formatting and checksumming via EIP-55, unit conversion between Wei and Ether, ABI encoding and decoding, cryptographic hashing via keccak256, signature creation and verification), and support for ENS (Ethereum Name Service) resolution. The library handles all EVM-compatible chains including Ethereum mainnet, Layer 2 networks (Arbitrum, Optimism, Base, Polygon), and test networks. As of 2026, ethers.js has over 8,000 GitHub stars and over 3 million weekly npm downloads.