> For the complete documentation index, see [llms.txt](https://docs.pivotalchain.io/pivotal-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pivotalchain.io/pivotal-docs/pivotalchain-tools/clients/web3.js.md).

# web3.js

[web3.js](https://web3js.org/) is a JavaScript library that allows developers to interact with EVM-compatible blockchain networks.

You can use web3.js to interact with smart contracts deployed on the Base network.

***

### Install[​](https://docs.base.org/docs/tools/web3#install) <a href="#install" id="install"></a>

To install web3.js run the following command:

```
npm install web3
```

### Setup[​](https://docs.base.org/docs/tools/web3#setup) <a href="#setup" id="setup"></a>

Before you can start using web3.js, you need to import it into your project.

Add the following line of code to the top of your file to import web3.js:

```
//web3.js v1
const Web3 = require('web3');

//web3.js v4
const { Web3 } = require('web3');
```

### Connecting to Pivotal[​](https://docs.base.org/docs/tools/web3#connecting-to-base) <a href="#connecting-to-base" id="connecting-to-base"></a>

You can connect to Pivotal by instantiating a new web3.js `Web3` object with a RPC URL of the Base network:

```
const { Web3 } = require('web3');

const web3 = new Web3('https://mainnet.thepivotal.xyz');
```

{% hint style="info" %}
To alternatively connect to Pivotal Sepolia (testnet), change the above URL from `https://mainnet.thepivotal.xyz` to `https://sepolia.thepivotal.xyz`.
{% endhint %}

### Accessing data[​](https://docs.base.org/docs/tools/web3#accessing-data) <a href="#accessing-data" id="accessing-data"></a>

Once you have created a provider, you can use it to read data from the Pivotal network.

For example, you can use the `getBlockNumber` method to get the latest block:

```
async function getLatestBlock(address) {
  const latestBlock = await web3.eth.getBlockNumber();
  console.log(latestBlock.toString());
}
```

### Deploying contracts[​](https://docs.base.org/docs/tools/web3#deploying-contracts) <a href="#deploying-contracts" id="deploying-contracts"></a>

Before you can deploy a contract to the Pivotal network using web3.js, you must first create an account.

You can create an account by using `web3.eth.accounts`:

```
const privateKey = “PRIVATE_KEY”;
const account = web3.eth.accounts.privateKeyToAccount(privateKey);
```

{% hint style="info" %}
`PRIVATE_KEY` is the private key of the wallet to use when creating the account.
{% endhint %}

### Interacting with smart contracts[​](https://docs.base.org/docs/tools/web3#interacting-with-smart-contracts) <a href="#interacting-with-smart-contracts" id="interacting-with-smart-contracts"></a>

You can use web3.js to interact with a smart contract on Pivotal by instantiating a `Contract` object using the ABI and address of a deployed contract:

```
const abi = [
… // ABI of deployed contract
];

const contractAddress = "CONTRACT_ADDRESS"

const contract = new web3.eth.Contract(abi, contractAddress);
```

Once you have created a `Contract` object, you can use it to call desired methods on the smart contract:

```
async function setValue(value) {
  // write query
  const tx = await contract.methods.set(value).send();
  console.log(tx.transactionHash);
}

async function getValue() {
  // read query
  const value = await contract.methods.get().call();
  console.log(value.toString());
}
```

{% hint style="info" %}
For more information on deploying contracts on Pivotal, see [Deploying a Smart Contract](/pivotal-docs/build-on-pivotalchain/pivotal-contracts.md).
{% endhint %}