What is theta.js?

The theta-js library aims to be a complete and compact library for interacting with the Theta Network Blockchain and its ecosystem.

In addition to the raw RPC API, we have also provided a JavaScript SDK to make it easier for DApps to interface with the Theta blockchain. The functionality is similar to Ethereum’s web3.js and is aiming to provide a developer-friendly framework for DApps to interact with the Theta blockchain. Through the SDK, a DApp can easily query for blocks and transactions, sign and issue transactions to the blockchain, as well as deploy and interact with smart contracts. The SDK can also be used as an automated unit test framework for the developers to thoroughly test and validate the functionalities of their smart contracts before production deployment.

Note: Since the July 2021 v3.1.0 release, Theta becomes fully EVM-compatible, and supports the entire Etherum DApp dev stack including Metamask, Hardhat, Remix, Ethers.js, Web3.js, and Truffle Suite. Thus, as an alternative to the theta-js lib, you can also use the Ethereum DApp dev suite to develop your DApps. Please click here to learn more.


  • Keep your private keys in your client, safe and sound
  • Import and export JSON wallets
  • Import and export BIP 39 mnemonic phrases (12 word backup phrases) and HD Wallets
  • Meta-classes create JavaScript objects from any contract ABI, including ABIv2 and Human-Readable ABI
  • Connect to Theta nodes over JSON-RPC

What’s Next