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Harmony
Harmony (ONE) is an EVM-compatible sharded Layer 1 secured by Effective Proof of Stake, a staking mechanism designed specifically for validator selection across its shard-based architecture. Solidity contracts execute through the EVM against account-based state, while nodes validate shard blocks, execute transactions, and maintain balances, contract storage, validator data, and cross-shard state. This combination preserves Ethereum-style contract semantics while adding Harmony-specific shard and staking objects, so integrations use familiar JSON-RPC concepts alongside network-specific methods.
Harmony API Methods and Endpoints
NOWNodes exposes Harmony's interface, plus a few others, depending on what your integration needs: JSON-RPC for reading chain state and broadcasting transactions. Archive mode extends any of these to historical states and data beyond standard retention.
Browse the interfaces below for endpoint details, request parameters, response formats, and integration examples. Create an API key, select Mainnet or Testnet, choose the required interface, and start sending requests from your application.
Weighing Harmony RPC providers against each other? Read the comparison guide on our blog — this page stays focused on integration reference.
Quick start
Select environment
Mainnet or Sepolia testnet.
Choose an interface
RPC, WSS, Blockbook, or Trace/Debug.
Send a request
Call it from your application.
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