What this API does
The Covalent API is designed to allow developers to query extensive on-chain data across 200+ blockchains. It enables access to wallet balances, NFT metadata, transaction histories, DeFi positions, and token transfers. The API returns standardized JSON responses, facilitating seamless integration into web and mobile applications.
How it works
This API operates via a RESTful interface. Developers send HTTP GET requests to obtain various blockchain data, including wallet balances and NFT details. Each request returns data in JSON format, simplifying integration with development environments. Common requests include fetching token balances for a wallet or retrieving metadata for NFTs.
Authentication
Authentication is managed through API keys, which can be obtained quickly via the Covalent dashboard. Users can register without needing a credit card. This straightforward setup allows developers to start integrating blockchain data into their projects rapidly.
Example usage
/v1/{chain_id}/address/{address}/balances_v2/- Retrieves token balances for a specified wallet address./v1/{chain_id}/tokens/{contract_address}/- Fetches NFT metadata based on contract address./v1/{chain_id}/address/{address}/transactions/- Lists transaction history for a specified wallet address./v1/{chain_id}/portfolio/{address}/- Gathers data on DeFi positions for a wallet.
Limits
The Covalent API allows for 100,000 free requests per month. Additional usage may require upgrading to a paid plan for expanded features and request limits, but basic functionality remains accessible without credit card requirements.
Ideal use cases
- Building multi-chain wallets that manage assets across various blockchains.
- Creating NFT marketplaces that require metadata lookup for various tokens.
- Developing analytics tools that assess DeFi positions for users.
- Integrating real-time transaction monitoring into blockchain applications.