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Chain ID

A chain ID is a unique identifier that represents a blockchain network. We use it to distinguish different blockchain networks from each other and to ensure that transactions and messages are sent to the correct network. Evmos network follows the format of identifier_EIP155-version format.

Official Chain IDs

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NOTE: The latest Chain ID (i.e highest Version Number) is the latest version of the software and mainnet. Also note, that the following upgrades technically did not require a Chain ID change:

  • evmos_202002-1 -> evmos_202002-2
  • evmos_202002-3 -> evmos_202002-4

Mainnet

NameChain IDIdentifierEIP155 NumberVersion NumberActive
DEP 2202002evmos2020022

Testnet

NameChain IDIdentifierEIP155 NumberVersion NumberActive
DEP Public Testnetevmos_808008-4evmos8080084
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You can also lookup the EIP155 Chain ID by referring to chainlist.org.

The Chain Identifier

Every chain must have a unique identifier or chain-id. Tendermint requires each application to define its own chain-id in the genesis.json fields. However, in order to comply with both EIP155 and Cosmos standard for chain upgrades, Evmos-compatible chains must implement a special structure for their chain identifiers.

Structure

The DEP Chain ID contains 3 main components

  • Identifier: Unstructured string that defines the name of the application.
  • EIP155 Number: Immutable EIP155 CHAIN_ID that defines the replay attack protection number.
  • Version Number: Is the version number (always positive) that the chain is currently running. This number MUST be incremented every time the chain is upgraded or forked in order to avoid network or consensus errors.

Format

The format for specifying and DEP compatible chain-id in genesis is the following:

{identifier}_{EIP155}-{version}

The following table provides an example where the second row corresponds to an upgrade from the first one:

ChainIDIdentifierEIP155 NumberVersion Number
evmos_202002-1evmos2020021
evmos_202002-2evmos2020022
............
evmos_202002-Nevmos202002N