Data API Reference

New CU Costs

Build and scale apps with lower CU costs on key APIs

How CU costs work

NFT API

Alchemy’s NFT API allows you to quickly get all the information you need to know about NFTs from the blockchain including Ethereum and Polygon.

Rather than searching, indexing, and storing data yourself - you can now make one request to fetch specific NFT information for both ERC-721 and ERC-1155 tokens, like:

• All NFTs owned by an address
• Metadata and attributes for a specific NFT token

NFT API Tutorials

• How to Resolve ENS Domains Given a Wallet Address

Transfers API Endpoints

Transfers are a representation of value being exchanged between two accounts, and sometimes users wish to see the historical transactions associated with a specific account or address.

Getting historical transactions is currently an extremely challenging and inefficient task, requiring users to scan the entire blockchain and index everything to search for transactions associated with the desired address.

With the Transfers API, users can query all historical transactions for an address in one request!

Transfers API Tutorials

• How to Get Transaction History for an Address on Ethereum
• How to get historical transactions on Polygon
• How to Get All NFTs Owned by an Address
• How to Get NFTs Minted by an Address

Transaction Receipts API

Fetch all transaction receipts for a block number or a block hash in one API call using the alchemy_getTransactionReceipts method - for mainnet and testnets on Ethereum, Polygon, Optimism, and Arbitrum.

The Transaction Receipts API uses less Compute Units (CUs) then batching all the eth_getTransactionReceipt calls for each transaction hash - saving you on compute cost.

Token API

Easily request information on specific tokens such as metadata or balances.

Alchemy currently supports the following endpoints:

• alchemy_getTokenAllowance - returns the amount the spender is allowed to withdraw from the owner.
• alchemy_getTokenBalances - returns token balances for a specific address given a list of contracts.
• alchemy_getTokenMetadata - returns metadata (name, symbol, decimals, logo) for a given token contract address.

Token API Tutorials

• How to Get Token Metadata
• How to Get Token Balance for an Address

Notify API

Alchemy provides a set of webhooks for tracking address activity, mined transactions, dropped transactions, and gas prices on several blockchains.

Developers can manually create webhooks from within the dashboard, or programmatically create webhooks to track activity for 10+ addresses using the Notify API.

Notify API Tutorials

• Notify API Quickstart
• How to Integrate Alchemy Webhooks with Zapier
• Building a dApp with Real-Time Transaction Notifications

Trace API Endpoints

Trace API methods give developers access to the most detailed information about on-chain activity, and allow users to get a full externality trace on any transaction executed on Ethereum.

Unlike the log filtering API, you are able to search and filter based only upon address information.

Information returned includes the execution of all CREATE, SUICIDE and all variants of CALL together with input data, output data, gas usage, the amount transferred, and the success status of each individual action.

Subscription API

Alchemy allows you to subscribe for push updates via Websockets on a variety of real-time alerts, such as pending transactions, log events, new blocks and more!

Subscription API Tutorials

• How to Listen to NFT Mints

Summary

Token, NFT, Prices APIs

Token APIs	NFT APIs	Prices APIs
Ideal for: Multi-chain token experiences, balance indexing How it works: Simply call an API to return multi-chain and complete token data	Ideal for: NFT drops, token gating, analytics, wallets, marketplaces How it works: Simply call an API to return multi-chain and complete NFT data.	Ideal for: Multi-chain token experiences, trading apps, wallets How it works: Simply call an API to return multi-chain and complete token prices data.

Webhooks

Webhooks	Custom Webhooks
Ideal for: Push notifications, wallets, consumer facing apps How it works: Define your Webhook and start receiving relevant events	Ideal for: Infinite customization, specific data needs, multi-chain apps How it works: Customize your event to your exact needs and immediately receive them.

Ship lightning fast with Subgraphs

Leverage Alchemy Subgraphs to ship features as soon as possible, simplify your infrastructure, and not worry about scaling.

Subgraphs	Community
Ideal for: Scaling existing Subgraphs, moving quickly with Subgraph indexing How it works: Define your Subgraph, let Alchemy handle the infra, and query via GraphQL	Ideal for: Immediate data querying, common use-cases How it works: Select a community Subgraph and immediately start querying via GraphQL.