Nethereum

Nethereum

Nethereum is the .NET integration platform for Ethereum and EVM-compatible blockchains. It provides a complete development stack — from smart contract interaction and transaction signing, through a full EVM simulator and in-process Ethereum node, to blockchain data indexing, an ERC-4337 account abstraction bundler, a Blazor blockchain explorer, MUD framework support, multi-platform wallet UIs, Unity game integration, and .NET Aspire orchestration. Nethereum targets netstandard 2.0 through .NET 10, .NET Framework 4.5.1+, and Unity, running on Windows, Linux, macOS, Android, iOS, WebAssembly, and game consoles.

Try Nethereum in Your Browser

Go to playground.nethereum.com to browse and execute samples directly in your browser — no setup required.

Quick Start

dotnet add package Nethereum.Web3

Get an account balance

var web3 = new Web3("https://mainnet.infura.io/v3/YOUR_API_KEY");
var balance = await web3.Eth.GetBalance.SendRequestAsync("0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae");
Console.WriteLine($"Balance: {Web3.Convert.FromWei(balance.Value)} ETH");

Transfer ETH

var account = new Account("YOUR_PRIVATE_KEY");
var web3 = new Web3(account, "https://mainnet.infura.io/v3/YOUR_API_KEY");

var receipt = await web3.Eth.GetEtherTransferService()
    .TransferEtherAndWaitForReceiptAsync("0xRecipientAddress", 0.01m);

Interact with a smart contract

// Use code-generated typed services (see Code Generation below)
var transferHandler = web3.Eth.GetContractTransactionHandler<TransferFunction>();
var receipt = await transferHandler.SendRequestAndWaitForReceiptAsync(contractAddress,
    new TransferFunction { To = recipientAddress, Value = amount });

What You Can Build

Nethereum includes 130+ packages organised into focused libraries. Every row below links to a how-to guide on the documentation site.

Core Foundation

I want to...	Guide
Query ETH, ERC-20, ERC-721, and ERC-1155 balances (built-in typed services, no ABI needed)	Query Balance
Send ETH (gas, nonce, EIP-1559 fees — all automatic)	Transfer Ether
Send a transaction with custom data or fees	Send Transactions
Delegate an EOA to a smart contract (EIP-7702)	EIP-7702
Query blocks, transactions, and receipts	Query Blocks
Estimate and customize gas fees	Fee Estimation
Replace or speed up a pending transaction	Transaction Replacement
Decode function calls from transaction input data	Decode Transactions
ABI encode/decode (abi.encode, abi.encodePacked, EIP-712)	ABI Encoding
Stream real-time data (new blocks, pending txns, event logs)	Real-Time Streaming

Signing & Key Management

I want to...	Guide
Generate keys and create accounts	Keys & Accounts
Sign and verify messages	Message Signing
Sign EIP-712 typed structured data	EIP-712 Signing
Use HD wallets (BIP32/BIP39 mnemonic)	HD Wallets
Sign with Ledger or Trezor hardware wallets	Hardware Wallets
Sign with AWS KMS or Azure Key Vault	Cloud KMS

Smart Contracts

I want to...	Guide
Deploy, call, and send transactions to contracts	Smart Contract Interaction
Work with ERC-20 tokens (balance, transfer, approve)	ERC-20 Tokens
Generate C# services from Solidity ABI	Code Generation
Filter and query contract events	Events
Batch queries with Multicall or RPC batching	Multicall
Deploy to deterministic addresses with CREATE2	CREATE2

EVM Simulator

I want to...	Guide
Simulate a transaction and preview state changes	Transaction Simulation
Debug EVM execution step-by-step (opcodes, stack, storage)	EVM Debugging
Decode nested call trees (contract-to-contract calls)	Call Tree Decoding
Simulate ERC-20 transfers and approvals	ERC-20 Simulation
Execute and disassemble raw bytecode	Bytecode Execution

DevChain & Local Development

I want to...	Guide
Run a local dev chain (no external node needed)	DevChain Quickstart
Fork a live network and manipulate state/time	Forking & State
Trace and debug transactions (opcode-level)	Debug & Trace
Spin up a full dev environment with Aspire (DevChain + PostgreSQL + Indexer + Explorer)	dotnet new nethereum-devchain

DeFi & Protocols

I want to...	Guide
Swap tokens on Uniswap (V2/V3/V4)	Uniswap Swap
Manage Uniswap liquidity positions	Uniswap Liquidity
Execute Gnosis Safe multi-sig transactions	Gnosis Safe
Accept or pay for crypto payments (x402)	x402 Payments

Account Abstraction

I want to...	Guide
Create and send a UserOperation	Send UserOperation
Deploy a smart account	Smart Account Deployment
Batch operations and use paymasters	Batching & Paymasters
Use ERC-7579 modular accounts (validators, hooks, session keys)	Modular Accounts
Run an ERC-4337 bundler	Run Bundler

Data, Indexing & Explorer

I want to...	Guide
Index blockchain data to PostgreSQL / SQL Server / SQLite	Database Storage
Index ERC-20/721/1155 token transfers and balances	Token Indexing
Build a blockchain explorer (ABI decoding, token pages, contract interaction)	Blockchain Explorer
Scan token balances via multicall (no indexer needed)	Token Portfolio
Fetch ABI from Sourcify or Etherscan	ABI Retrieval
Get token prices and metadata (CoinGecko)	CoinGecko API

MUD

I want to...	Guide
Read, write, and query MUD table records	MUD Tables
Index MUD Store events to PostgreSQL	MUD Indexing
Deploy a MUD World with tables and systems	MUD Deployment

Wallet SDK · Blazor dApp · Unity

I want to...	Guide
Build a multi-platform wallet app (Blazor, MAUI, Avalonia)	Wallet Quickstart
Create accounts (mnemonic, private key, vault encryption)	Wallet Accounts
Connect browser wallets in Blazor (EIP-6963 discovery)	Blazor Wallet Connect
Authenticate with Sign-In with Ethereum (SIWE)	Blazor Authentication
Interact with any contract dynamically (no codegen)	Blazor Contract Interaction
Build Unity games with Ethereum	Unity Quickstart

Verification & Cryptography

I want to...	Guide
Verify ETH balances without trusting RPC	Verified State
Track finalized beacon headers via light client	Light Client

AppChains (Preview)

I want to...	Guide
Launch a sequencer and deploy contracts	AppChain Quickstart
Use AppChainBuilder for embedded/testing	AppChain Quickstart
Configure RocksDB persistent storage	[AppChain Storage](https://docs.nethereum.com/docs/a