Resources for Developers

Developer Support Channel

Developers are welcome to join the telegram channel for technical support.

Cronos Networks and resources

Explorer API keys

Explorer API keys for Cronos Chains are required to query block chain data, kindly follow the following instruction to obtain the API key for:

Cronos zkEVM

To get started with the Cronos zkEVM developer API, simply register an account on the Account Registration page in Cronos zkEVM developer portal, where you can access a pair of mainnet and testnet API keys on the user dashboard. You can then access the developer API service and use it to retrieve data from the available endpoints.

Cronos EVM

Kindly follow the instructions to obtain the API key for Cronos EVM

Documentation

For detailed documentation of Cronos Chain, kindly visit:

• Cronos zkEVM - https://docs-zkevm.cronos.org/

• Cronos EVM - https://docs.cronos.org/

Cronos zkEVM Mainnet URLs

• Chain ID: 388

• Token: zkCRO ("Cronos zkEVM CRO")

• JSON RPC API (rate limited): https://mainnet.zkevm.cronos.org

• WebSocket (rate limited): wss://ws.zkevm.cronos.org

• Blockchain explorer: https://explorer.zkevm.cronos.org/

• Gas price: ⚠️ The gas price is currently fixed at 1250 gwei

  • This is subject to change and is expected to be dynamic in the next major release to be announced.

• Developer portal: https://developers.zkevm.cronos.org/

• Contract verification interface: https://explorer.zkevm.cronos.org/verifyContract

• Bridge for ERC-20 tokens (Ethereum <=> Cronos zkEVM): https://zkevm.cronos.org/bridge

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Cronos zkEVM Sepolia Testnet URLs

• Chain ID: 240

• Token: zkTCRO

• JSON RPC API (rate limited): https://testnet.zkevm.cronos.org

• WebSocket (rate limited): wss://ws.testnet.zkevm.cronos.org

• Blockchain explorer: https://explorer.zkevm.cronos.org/testnet

• Gas price: ⚠️ The gas price of is currently fixed at 1250gwei

  • This is subject to change and is expected to be dynamic in the next major release to be announced.

• Developer portal: https://developers.zkevm.cronos.org/

• Contract verification interface: https://explorer.zkevm.cronos.org/testnet/verifyContract

• zkTCRO faucet: https://zkevm.cronos.org/faucet

• Demo project repository for smart contract developers

• Testnet bridge for ERC-20 tokens (zkEVM testnet <=> Ethereum Sepolia): https://zkevm.cronos.org/bridge/testnet

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Cronos EVM Mainnet URLs

• Chain ID: 25

• JSON RPC API: https://evm.cronos.org

• Block explorer: https://explorer.cronos.org/

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Cronos EVM Testnet URLs

• Chain ID: 338

• JSON RPC API: https://evm-t3.cronos.org/

• Block explorer: https://explorer.cronos.org/testnet

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