> For the complete documentation index, see [llms.txt](https://docs.usemeta.fi/react-sdk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usemeta.fi/react-sdk/constants/chain.md).

# Chain

## Description

The chain object defines chains in a format supported by the Metafi SDK.

## Structure

<table><thead><tr><th width="213">Field Name</th><th width="111">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>name</code></td><td>String</td><td>Name of the chain, eg. "Ethereum mainnet"</td></tr><tr><td><code>currencySymbol</code></td><td>String</td><td>Symbol of the native currency of the chain, eg. "ETH"</td></tr><tr><td><code>isTestnet</code></td><td>boolean</td><td>Whether or not the chain is a testnet</td></tr><tr><td><code>blockExplorerURL</code></td><td>String</td><td>Link to the chain block explorer</td></tr><tr><td><code>chainKey</code></td><td>String</td><td>Key for the chain in the <code>chains</code> object that is accessible from our SDK. for eg. "goerli"</td></tr><tr><td><code>chainID</code></td><td>Number</td><td>Chain ID of the chain - only for EVM compatible chains</td></tr><tr><td><code>rpcURL</code></td><td>String</td><td>RPC node URL of the chain</td></tr></tbody></table>

## Supported Chains

Currently, we support the following chains:

**Mainnets**

* Ethereum Mainnet : `chains.eth`
* Polygon Matic Mainnet : `chains.matic`

**Testnets**

* Görli (Goerli testnet) : `chains.goerli`&#x20;
* Mumbai testnet : `chains.mumbai`

We are working on supporting more chains - feel free to reach out via Discord if you require support for a different chain.

## Usage

```jsx
import { chains } from '@metafi/metafi-react-package';

function displaySupportedChains() {
    return (
        <>
            {
                Object.keys(chains).forEach((chainKey) => {
                    return <p> chains[chainKey].name </p>
                });
            }
        </>
    );
};
```