An EVM-compatible testnet, Harmony Testnet Shard 1 (Chain ID 1666700001) enables dApp and cross-shard testing with EPoS/FBFT consensus, 2-second finality, and low fees.
Harmony Testnet Shard 1 (chainId 1666700001) is an EVM-compatible shard of Harmony’s test network used to trial sharded execution, cross-shard messaging, and dApp tooling with free ONE test tokens. Teams use it to deploy and debug smart contracts, rehearse bridge and cross-shard transaction paths, and run validator and performance tests before mainnet. Typical metrics: ~2s block time/finality, ~100–200+ TPS per shard in testing, and a simple transfer costs ~0.000021 ONE (≈21k gas at 1 gwei) with developer-driven, bursty activity.
It’s unique for offering native sharding with full EVM compatibility, so cross-shard transactions and receipts are handled at the protocol layer—no external rollups required. With FBFT consensus it delivers ~2s blocks and near-instant finality, and low, stable gas prices (commonly ~1 gwei; e.g., ~0.000021 ONE for a transfer), which is faster and cheaper than typical L1 EVM testnets. For cross-chain builders, it integrates cleanly with Harmony developer tooling and bridge workflows, enabling realistic load tests (100+ TPS per shard) and end-to-end pre-production benchmarking.
Harmony Testnet Shard 1 uses ONE as the gas token for transaction fees. You can obtain ONE by bridging from other chains or purchasing using thirdweb Bridge, or through faucets (for testnet).
To bridge ONE to Harmony Testnet Shard 1, connect your wallet to thirdweb bridge, select your source chain, choose the token you want to bridge, select Harmony Testnet Shard 1 as the destination, enter the amount, and confirm the transaction. The bridge will handle the cross-chain transfer instantly.
To build on Harmony Testnet Shard 1 you can use thirdweb, which provides an easy way to build, monetize and scale your apps, games or agents. You can find detailed guides and documentation on https://portal.thirdweb.com to get started quickly.
To add Harmony Testnet Shard 1 to your wallet, you can connect your wallet and click on [Add to Wallet] button at the top of the page. Alternatively, you can add the network manually using the RPC URL and chain details and add it to your wallet's network settings.
To send ONE on Harmony Testnet Shard 1, ensure your wallet is connected to the Harmony Testnet Shard 1 network, enter the recipient's address, specify the amount of ONE to send, review the gas fee, and confirm the transaction in your wallet.
