Ethereum Mainnet

Overview

Why Ethereum Mainnet matters

Ethereum enables applications to run shared programs in addition to transferring its native asset, ether (ETH). This capability powers many stablecoins and payment-related token contracts. For a merchant, the distinction between ETH and ERC-20 tokens is important because both can be present on Ethereum but require different transaction processing and event checks.

How it works

An Ethereum externally owned account authorizes a transaction using its private key. The transaction includes a chain-specific nonce, gas parameters, destination and optional input data. If it transfers ETH, the account balances update; if it invokes a token contract, the EVM executes contract code and may emit Transfer events. The network charges execution fees in ETH. Validators propose and attest to blocks, and the consensus protocol establishes finalized checkpoints. Successful inclusion is not the same as successful contract execution: reverted calls consume gas without delivering the intended token. Layer-2 rollups may execute user transactions separately and post commitments or data to Ethereum, creating additional timing and withdrawal considerations.

Gas and token value are separate quantities

Suppose a customer holds exactly 100 units of an ERC-20 stablecoin but no ETH. The token contract may show enough balance to pay a 100-unit invoice, yet the customer may not be able to submit a standard transfer because the Ethereum network charges gas in ETH. The required fee depends on gas consumed and transaction fee parameters, not directly on the dollar value of tokens sent. A failed contract call may still incur gas costs. This is why a checkout should distinguish the amount owed to the merchant from network resources needed by the payer. It should also verify token movement by checking the intended contract and receipt, because an apparently valid Ethereum transaction can call unrelated code or revert.

A real-world payment example

A store accepts USDC on Ethereum Mainnet. The buyer pays using an ERC-20 transfer rather than a plain ETH transfer. The store verifies the official token contract and event arguments plus adequate finality. If the buyer sends a different token with the same symbol, an explorer's success label does not make it the correct payment.

Limits and common misunderstandings

Mainnet gas fees change with network demand, and the sender normally needs ETH even to transfer a non-ETH token unless another approved abstraction pays fees. Incorrect token approvals and malicious contracts are additional risks. A network called "Ethereum-compatible" is not necessarily Ethereum Mainnet.

How it differs from related concepts

Ethereum Mainnet is the layer-1 ledger. ETH is its native currency. ERC-20 is a token interface standard; Arbitrum One and similar networks are separate systems connected to Ethereum.

Explore further

Official background: technical documentation.

Related glossary terms: Ethereum, ERC-20, Gas Fee.