What Is Ethers.js?

Developed by Richard Moore, the library is organized around a few core concepts. A provider connects to an Ethereum node over JSON-RPC and reads data such as blocks, balances, and contract state. A signer is the component that has access to a private key and signs transactions; this can be a browser wallet or a key on a server. The contract object uses the contract's interface definition (ABI) to let functions be called like ordinary JavaScript methods.

The library also offers helper tools such as unit conversion (for example, between wei and ether), address validation, message signing, and ENS domain name resolution. With its small size and comprehensive documentation, it is frequently used in decentralized application front ends, bots, and test scripts in development environments such as Hardhat. Version 6 moved to JavaScript's native BigInt type for large numbers. Its alternatives include web3.js and viem.

When working with Ethers.js, a basic security rule is never to include private keys or recovery phrases in front-end code or public code repositories. Because there are breaking changes between major versions of the library, you should also check that old sample code is compatible with the version you are using.