Guides
The following guides show you how to solve a specific problem or use case using the Covalent Unified API.
Token Balances
Understanding Web3 Wallets with Covalent
An explanation for Web3 developers on what Web3 wallets are and how to build them leveraging Covalent's blockchain API.
Comparing Covalent’s Token Balances API to RPC Providers
This comparison between Covalent and RPC providers shows that Covalent's API offers a more efficient solution for developers to access blockchain data.
Building Web3 Wallets (Part 1) - Token Displays
Ever wondered how you can build a Web3 wallet like Metamask or Coinbase wallet? Covalent has endpoints that allow you to do it easily.
Building Web3 Wallets (Part 2) - Curve LP Token Balances
Ever wondered how to get the balances of all your Curve LP tokens, along with rewards? You can do it easily with Covalent API.
How to Get Token Holder Data for ERC-20, ERC-721 and ERC-1155s
Use the Covalent API to easily fetch a complete list of token holders for different types of tokens across any supported blockchain.
Building Web3 Wallets (Part 5) - Revoking Approvals for Your Wallet
Have you ever felt uneasy about the different dApps you've approved? In this guide, we'll build an 'approvals checker' with the Covalent API.
How to Build a 30-Day Historic Crypto Portfolio Chart
Have you ever wondered how you can track the historic value of your crypto holdings for the last 30/60/90 days or longer? With the Covalent API..
Building Web3 Wallets (Part 6) - Multi-chain Portfolio Tracker
In this guide, you'll learn how you can build a multi-chain portfolio tracker that fetches tokens across 100+ chains in less than 15 minutes.
Transactions
Scaling Transactions API with Time Buckets
Explore Covalent's time buckets for efficient transaction retrieval. Utilize 15-minute intervals for precise, scalable data access.
How to Get All Historical Transactions in a Block
Getting all transactions on historical blocks on 100+ chains including fully decoded event logs.
Introducing Transactions V3 APIs
A guide to the new v3 suite of Transaction APIs including paginating through large contracts with millions of transactions.
How to Flag Interesting Wallets or Transactions
Ever wondered how you can build something like Nansen's Smart Alerts, or the Whale Alert bot on Twitter? Look no further.
Understanding Different Types of Blockchain Transactions with Covalent
Learn about the different types of blockchain transactions and how Covalent provides historical on-chain data.
How to Get Bitcoin Balances and Transactions
Easily fetch balances and transactions for a Bitcoin wallet using the Covalent API.
Building Web3 Wallets (Part 3) - Displaying Curve Transactions
Have you wondered how you can easily retrieve all your transactions on a DeFi protocol like Curve? In this part, we'll build a React component to do that.
Building Web3 Wallets (Part 4) - Displaying Curve Liquidity Pools
Ever wondered how you can display all the liquidity pools on Curve, their supply APY, TVL, as well as each pool's token balance? With Covalent API, you can.
Discover Your Ethereum Gas Consumption with the Covalent API
Take a deep dive into your Ethereum gas consumption with the help of the Covalent API.
How to Get the Latest Axie Spawns
Ever wondered how you can get in-depth GameFi data? With the Covalent API, you can easily get in-game actions like Axie breed events.
Building Web3 Wallets (Part 7) - Multi-Chain Wallet Activity Summary
Ever wondered how you can get the total transaction count, earliest, or latest transaction of an address? With Covalent's brand new endpoint, it is easy.
Building Block Explorers (Part 1) - Multi-chain Block Transaction Explorer
In this tutorial, you'll learn how to build a multi-chain block transactions explorer with the Covalent API in less than 30 minutes.
Calculate Crypto Cost Basis and Capital Gains with Covalent
Calculate your crypto cost basis and capital gains in minutes with Covalent's easy-to-use, customizable tool!
Building with Account Abstraction (Part 2) - Creating UserOps
This guide will walk through how developers can create UserOperations using the Stackup and Biconomy SDKs tailored for Account Abstraction.
How to Fetch User Operations (UserOps) for a Specific Wallet Address
This guide teaches you how to efficiently filter and retrieve UserOps (account abstraction transactions) pertaining to a particular user.
NFTs
Seeking NFT Alpha with Covalent
Using the Covalent API, fetch traits and attributes for any NFT on supported chains and build NFT rarity features!
How to Get All Transfers for an NFT
Using Covalent's easy on-chain NFT APIs, get transaction history and many more NFT data points.
How to Verify NFT Ownership in a Collection
Learn how to verify NFT ownership as a developer to build tools for exclusive access, rewards, information and more.
From Wallet to Web: Displaying NFT Holdings with Covalent's NFT Endpoints
This guide will show you how to utilize Covalent's NFT endpoints to create visual representations of NFT holdings in a wallet!
How to Block Spam NFT Tokens
Is your Web3 wallet littered with NFT spams? No fret - you can block NFT spams easily with the Covalent API.
How to Create an NFT Allowlist
This is a step-by-step guide on NFT Allowlists and how to create them with Solidity smart contracts.
EIP-2981: Implementing NFT Royalties On-Chain
This guide describes NFT royalties in Web3 and how to implement them via smart contracts.
Mastering the ERC-1155 Multi-Token Standard (Part 1)
This article provides a comprehensive overview of ERC-1155, the Multi-Token Standard, and how it differs from ERC-20 and ERC-721 tokens.
Mastering the ERC-1155 Multi-Token Standard (Part 2)
Learn how to create, mint, deploy, and interact with an ERC-1155 smart contract.
What Are Dynamic NFTs and Why Do They Matter?
What are dynamic NFTs, what makes them dynamic, and how are they currently used in Web3? Read this guide to understand.
How to Create a Dynamic NFT
This guide teaches you how to deploy a dynamic NFT smart contract, connect to Chainlink keepers, and view the dynamic NFT on Opensea!
A Complete Guide to ERC-6551: Token Bound Accounts
Understand ERC-6551 Token Bound Accounts and follow along to implement your own with this step-by-step tutorial.
Other
A Guide to DeFi Taxes
Understand the difference between DeFi and CeFi, the different types of DeFi taxes, and what kinds of data are required for DeFi tax reporting.
Understanding Appchains with Covalent
Learn about application-specific blockchains (appchains) with Covalent, the leading indexer of appchains and a popular Web3 development platform.
Introduction to Class C Endpoints
Try Covalent's new protocol-specific endpoints to get DeFi market data on top Web3 protocols like Aave, Compound and more.
Understanding Covalent’s xy=k Endpoints
Explore how Covalent's xy=k endpoints empower developers to build an array of applications, bringing even more possibilities to the DeFi landscape
Understanding Account Abstraction
Learn all about account abstraction in the Ethereum ecosystem: what it is, benefits and use cases and more.
How to Get Test Tokens from Covalent's Testnet Faucet
If you're a developer exploring ecosystems like Linea or Base and need some test tokens, Covalent's testnet faucet has got you covered.
Building with Account Abstraction (Part 1) - Creating Smart Contract Accounts
Understanding the Sender Field Using Smart Contract Accounts in ERC 4337.
How to Clone UniswapV2 (Backend)
In this tutorial, we'll guide you through the process of cloning UniswapV2 and also provide insights into how the UniswapV2 contract operates.
Getting Started with the Covalent SDK
The Covalent SDK is a one-stop solution for access to blockchain data, including token balances, historical transactions, NFT metadata and more.
The Ultimate Guide to Top ERC-4337 Account Abstraction SDKs
Explore ERC-4337 with our guide: Dive into top SDKs like Alchemy's, understand Account Abstraction, and enhance your dApp's user experience.
Understanding Merkle Patricia Tries in Ethereum
This guide explains Merkle Patricia Tries in depth and how they solve for data storage challenges and data integrity on the Ethereum blockchain.
What Are DAOs and How Do They Work?
This guide walks you through Decentralized Autonomous Organizations (DAOs) and how they work, including the blockchain infrastructure and voting mechanisms.
How to Clone UniswapV2 (Frontend)
This guide teaches you how to clone the UniswapV2 frontend and connect it with a deployed smart contract on any EVM blockchain.
How To Create a DAO with Smart Contracts
In this practical guide, you will discover how to create a smart contract for an NFT DAO using the OpenZeppelin Governor contract.
How Layer 2 Blockchains Solve Ethereum’s Scalability Dilemma
This guide provides an overview of Layer 2 blockchains, Ethereum's scalability challenges, and how L2s improve performance and drive adoption.
How to Implement Merkle Patricia Tries in Ethereum
This practical guide offers a step-by-step implementation of a Merkle Patricia Trie, its architecture, and future trends and considerations.
How to Calculate Impermanent Loss (with Examples)
A step-by-step guide on how to understand and calculate impermanent loss that takes place on AMMs, with specific considerations for UniswapV3.
Building with Account Abstraction (Part 3) - Using the Paymaster Contract
This installment of our Account Abstraction series focuses on using the Paymaster contract in preparation to create a gasless dapp!
What is an Ethereum Contract Address and How Do You Find It?
You don’t need a programming background to get information from an Ethereum contract address, but you do need to know where to look. Read to find out!
The Ultimate RainbowKit Integration Tutorial for Web3 Developers
Follow our detailed guide on integrating RainbowKit into your dApps. From setup to execution, learn everything you need for successful wallet integration.
Building with Account Abstraction (Part 4) - Paymaster User Interface
Follow along in this detailed step-by-step tutorial to create a gasless dApp using Paymasters as part of our Account Abstraction guide series.
How to Set Up a (Gnosis) Safe Wallet Step-by-Step
Learn about the importance of Safe for security in Web3 and how you can set up your own Safe smart contract wallet.