# CrossFi API FAQ

> Frequently Asked Questions about the CrossFi API

> For the complete documentation index, see [llms.txt](/docs/llms.txt).

## What is CrossFi?

CrossFi is a blockchain platform designed to enable cross-chain interoperability and decentralized finance (DeFi) solutions. It provides a robust infrastructure for transferring assets between multiple blockchain networks, making it ideal for developers building decentralized applications (dApps) that require seamless cross-chain functionality.

## What is the CrossFi API?

The CrossFi API lets you interact with the CrossFi network through a set of JSON-RPC methods. It supports operations such as asset transfers across chains, smart contract deployment, and data retrieval, letting you integrate cross-chain functionality into your applications.

## How can I get started using the CrossFi API?

For a step-by-step guide, check out the [CrossFi API Quickstart](/docs/reference/crossfi-api-quickstart).

## Is CrossFi EVM compatible?

Yes, CrossFi is EVM-compatible, allowing you to deploy Ethereum-based smart contracts and applications on its network, while also supporting interoperability with other blockchain ecosystems.

## What API does CrossFi use?

CrossFi uses the JSON-RPC API standard, enabling efficient blockchain interactions. It provides a consistent and secure interface for cross-chain transactions and other decentralized operations.

## What is a CrossFi API key?

When accessing the CrossFi network via a service provider like Alchemy, you need an API key to send transactions and retrieve data. An API key provides secure and authenticated access to the network.

For the best development experience, we recommend that you [sign up for a free API key](https://dashboard.alchemy.com/signup).

## Which libraries support CrossFi?

CrossFi supports popular Ethereum-based libraries like Web3.js and Ethers.js, so you can leverage existing tools for cross-chain and DeFi applications.

## What programming languages work with CrossFi?

CrossFi supports Solidity for smart contract development due to its EVM compatibility. For offchain interactions, you can use JavaScript, TypeScript, or other widely-used web development languages.

## What does CrossFi use for gas?

CrossFi uses its native token, XFI, to pay for transaction fees, gas, and other network operations.

## What methods does Alchemy support for the CrossFi API?

You can find the full list of methods supported by Alchemy for the CrossFi API on the [CrossFi API Endpoints](/docs/chains#crossfi-apis) page.

## My question isn't here, where can I get help?

If you have any questions or feedback, contact us at support@alchemy.com or open a ticket in the Alchemy Dashboard.