The Leading Open-Source Developer Library for Ethereum
Web3j makes it easy to build Ethereum applications with Java and Android
What is Web3j?
Web3j is a highly modular, reactive, type safe Java and Android library for working with Smart Contracts and integrating with clients (nodes) on the Ethereum network.
This allows you to work with Ethereum blockchains, without the additional overhead of having to write your own integration code for the platform.
Getting started with Web3j
Run the following in your terminal, then follow the onscreen instructions
curl -L get.web3j.io | sh
web3j new
Head to the docs for more information.
Start building with Web3j
Contribute to Web3j
Sirato integration
Web3j integrates seamlessly with the Sirato Blockchain Explorer
Type safe
Web3j provides full type safe access to your blockchain applications
Build tool integration
Plugins for leading build tools to simplify the developer experience
Versatile CLI
Create projects to work with new or import existing decentralised apps in a single command with the Web3j CLI
Powerful integration testing
Simple to use framework for automated integration testing against networks within your IDE
Commercially supported OSS
Web3j is 100% open source and maintained by Web3 Labs
Dedicated support from the creators of Web3j





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