Configuring Hashio RPC endpoints

How to configure a JSON-RPC endpoint that enables communication between EVM-compatible developer tools using Hashio.

Hashio is a public RPC endpoint hosted by Hashgraph that runs an instance of the Hiero JSON-RPC Relay. As a public endpoint, it:

• Is free to use
• Does not have any sign-up requirements
• Has significantly restrictive rate limits

While this combination may be considered less reliable, it offers the highest levels of ease of use among RPC endpoints.

To connect to the Hedera networks via Hashio, simply use one of these URLs when initializing the wallet or web3 provider instance:

Mainnet

https://mainnet.hashio.io/api

The corresponding chain IDs are:

Network	Chain ID (decimal)	Chain ID (hex)
Mainnet	295	0x127
Testnet	296	0x128
Previewnet	297	0x129

No further settings or configurations are needed!

Please note: Hashio is for development and testing purposes only. Production use cases are strongly encouraged to use commercial-grade JSON-RPC relays or host their own instance of the Hiero JSON-RPC Relay.

Additional resources

• Hiero JSON-RPC Relay repository
• JSON-RPC Relay overview
• How to connect MetaMask to Hedera
• Add Hedera to MetaMask

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Editor: Krystal, Senior DX Engineer

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Editor: Logan, Senior Software Engineer

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