# Overview

OP Mainnet, formerly called Optimism, is the main blockchain network in the Optimism ecosystem.\
\
OP Mainnet is a Layer 2 network that operates on top of Ethereum's architecture. It is designed to be EVM equivalent and as close to Ethereum as possible.

The minor differences between building on OP Mainnet and Ethereum are outlined in [Optimism's developer docs](https://docs.optimism.io/chain/differences).

## Network Support

| Network           | HTTPS | WSS |
| ----------------- | ----- | --- |
| Mainnet           | ✅     | ✅   |
| Testnet (Sepolia) | ✅     | ✅   |

> WebSocket clients **MUST** respond to server `ping` frames, otherwise the connection will be closed and re-established every minute.

## Methods & Compute Units

<table data-header-hidden><thead><tr><th></th><th width="100"></th></tr></thead><tbody><tr><td>eth_accounts</td><td>10</td></tr><tr><td>eth_blockNumber</td><td>10</td></tr><tr><td>eth_call</td><td>30</td></tr><tr><td>eth_chainId</td><td>5</td></tr><tr><td>eth_estimateGas</td><td>100</td></tr><tr><td>eth_gasPrice</td><td>20</td></tr><tr><td>eth_getBalance</td><td>20</td></tr><tr><td>eth_getBlockByHash</td><td>30</td></tr><tr><td>eth_getBlockByNumber</td><td>20</td></tr><tr><td>eth_getBlockTransactionCountByHash</td><td>20</td></tr><tr><td>eth_getBlockTransactionCountByNumber</td><td>20</td></tr><tr><td>eth_getCode</td><td>20</td></tr><tr><td>eth_getFilterChanges</td><td>20</td></tr><tr><td>eth_getFilterLogs</td><td>70</td></tr><tr><td>eth_getLogs</td><td>80</td></tr><tr><td>eth_getStorageAt</td><td>20</td></tr><tr><td>eth_getTransactionByBlockHashAndIndex</td><td>20</td></tr><tr><td>eth_getTransactionByBlockNumberAndIndex</td><td>20</td></tr><tr><td>eth_getTransactionByHash</td><td>20</td></tr><tr><td>eth_getTransactionCount</td><td>30</td></tr><tr><td>eth_getTransactionReceipt</td><td>20</td></tr><tr><td>eth_getUncleByBlockHashAndIndex</td><td>20</td></tr><tr><td>eth_getUncleByBlockNumberAndIndex</td><td>20</td></tr><tr><td>eth_getUncleCountByBlockHash</td><td>20</td></tr><tr><td>eth_getUncleCountByBlockNumber</td><td>20</td></tr><tr><td>eth_newBlockFilter</td><td>20</td></tr><tr><td>eth_maxPriorityFeePerGas</td><td>20</td></tr><tr><td>eth_newFilter</td><td>20</td></tr><tr><td>eth_newPendingTransactionFilter</td><td>20</td></tr><tr><td>eth_sendRawTransaction</td><td>270</td></tr><tr><td>eth_subscribe</td><td>10</td></tr><tr><td>eth_syncing</td><td>5</td></tr><tr><td>eth_uninstallFilter</td><td>10</td></tr><tr><td>eth_unsubscribe</td><td>10</td></tr><tr><td>net_listening</td><td>5</td></tr><tr><td>net_peerCount</td><td>10</td></tr><tr><td>net_version</td><td>5</td></tr><tr><td>web3_clientVersion</td><td>10</td></tr><tr><td>web3_sha3</td><td>10</td></tr><tr><td>txpool_content</td><td>500</td></tr></tbody></table>