> For the complete documentation index, see [llms.txt](https://docs.facet.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.facet.org/reference/network-information.md).

# Network Information

**Chain IDs:**

* Mainnet: `1027303` (`0xface7` in hex)
* Sepolia: `16436858` (`0xface7a` in hex)

**Block Parameters:**

* Block time: 12 seconds (same as Ethereum)
* Gas limit: 200 million gas per block

**Block Explorers:**

* Mainnet: <https://explorer.facet.org>
* Sepolia: <https://sepolia.explorer.facet.org>

**RPC Endpoints:**

* Mainnet: <https://mainnet.facet.org/>
* Sepolia: <https://sepolia.facet.org/>

These endpoints support all read-only Ethereum JSON-RPC methods:

* `eth_estimateGas` - Estimate gas for transactions
* `eth_getBalance` - Query FCT balances
* `eth_getBlockByNumber` - Retrieve block data
* `eth_call` - Execute read-only contract calls
* And all other standard read methods

**Sending Transactions:** Facet transactions are sent through Ethereum L1. See [Sending Transactions](/immutable-sequencing/sending-transactions.md) for details.

**Pre-deployed Contracts:** See [Genesis Contracts](/reference/genesis-contracts.md) for the full list of contracts available at genesis.