> ## Documentation Index
> Fetch the complete documentation index at: https://docs.autheo.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Token contracts

> Deploy and interact with ERC-20 and ERC-721 token contracts on Autheo Chain.

Autheo Chain's EVM layer supports the full ERC-20 and ERC-721 standards. This tutorial shows how to deploy and interact with both token types using OpenZeppelin contracts.

## ERC-20 token

### Deploy

Use the [OpenZeppelin Wizard](https://wizard.openzeppelin.com/) to generate your contract or write from scratch:

```solidity theme={null}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

contract MyToken is ERC20, Ownable {
    constructor(address initialOwner)
        ERC20("MyToken", "MTK")
        Ownable(initialOwner)
    {
        _mint(msg.sender, 1_000_000 * 10 ** decimals());
    }

    function mint(address to, uint256 amount) external onlyOwner {
        _mint(to, amount);
    }
}
```

Deploy with Hardhat:

```bash theme={null}
npx hardhat run scripts/deploy.js --network autheoTestnet
```

### Interact with ethers.js

```javascript theme={null}
import { ethers } from "ethers";

const abi = [
  "function balanceOf(address) view returns (uint256)",
  "function transfer(address to, uint256 amount) returns (bool)",
  "function approve(address spender, uint256 amount) returns (bool)",
  "function allowance(address owner, address spender) view returns (uint256)",
  "event Transfer(address indexed from, address indexed to, uint256 value)"
];

const provider = new ethers.JsonRpcProvider("https://rpc1.autheo.com");
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
const token = new ethers.Contract(TOKEN_ADDRESS, abi, wallet);

// Check balance
const balance = await token.balanceOf(wallet.address);
console.log("Balance:", ethers.formatEther(balance), "MTK");

// Transfer tokens
const tx = await token.transfer("0x<recipient>", ethers.parseEther("100"));
await tx.wait(1);
console.log("Transferred in block:", (await tx.wait(1)).blockNumber);
```

## ERC-721 (NFT)

### Deploy

```solidity theme={null}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

contract MyNFT is ERC721, Ownable {
    uint256 private _nextTokenId;

    constructor(address initialOwner)
        ERC721("MyNFT", "MNFT")
        Ownable(initialOwner)
    {}

    function safeMint(address to) external onlyOwner returns (uint256) {
        uint256 tokenId = _nextTokenId++;
        _safeMint(to, tokenId);
        return tokenId;
    }
}
```

### Interact with ethers.js

```javascript theme={null}
const abi = [
  "function safeMint(address to) returns (uint256)",
  "function ownerOf(uint256 tokenId) view returns (address)",
  "function balanceOf(address owner) view returns (uint256)",
  "function transferFrom(address from, address to, uint256 tokenId)",
  "event Transfer(address indexed from, address indexed to, uint256 indexed tokenId)"
];

const nft = new ethers.Contract(NFT_ADDRESS, abi, wallet);

// Mint a new NFT
const tx = await nft.safeMint(wallet.address);
const receipt = await tx.wait(1);

// Find the token ID from the Transfer event
const transferEvent = receipt.logs
  .map(log => { try { return nft.interface.parseLog(log); } catch { return null; } })
  .find(e => e?.name === "Transfer");

const tokenId = transferEvent.args.tokenId;
console.log("Minted token ID:", tokenId.toString());

// Check owner
const owner = await nft.ownerOf(tokenId);
console.log("Owner:", owner);
```

## EVM version note

<Warning>
  Compile with `evmVersion: "paris"` to ensure compatibility with Autheo Chain. Using `shanghai` or later may cause deployment failures.
</Warning>

## Next steps

* [Interact with contracts](/developers/tutorials/interact-with-contracts) — general contract interaction patterns
* [Events and logs](/developers/tutorials/events-and-logs) — track Transfer events and other token activity
* [Indexing and analytics](/developers/tutorials/indexing-and-analytics) — build a token balance tracker