;
};
# ethers v6 Quickstart
This example covers ethers v6 with Sei. The patterns apply whether you are writing a Node.js script, a CLI tool, or a browser app.
## Install
```bash theme={"dark"}
npm install ethers
```
These snippets are TypeScript. Run any of them with no separate build step using [`tsx`](https://www.npmjs.com/package/tsx) (Node 18+):
```bash theme={"dark"}
npx tsx script.ts
```
## Read-Only Provider
```ts theme={"dark"}
import { ethers } from 'ethers';
const provider = new ethers.JsonRpcProvider('https://evm-rpc.sei-apis.com');
```
## Reading Chain Data
This is the first milestone — it needs no private key.
```ts theme={"dark"}
// Any valid Sei EVM address — swap in your own
const address = '0x0000000000000000000000000000000000000000';
const blockNumber = await provider.getBlockNumber(); // number
console.log('Block number:', blockNumber);
const balance = await provider.getBalance(address); // bigint, wei
console.log('Balance (SEI):', ethers.formatEther(balance));
const nonce = await provider.getTransactionCount(address); // number
console.log('Nonce:', nonce);
```
**You're done when you see:**
```text theme={"dark"}
Block number: 148203117
Balance (SEI): 12.5
Nonce: 7
```
The exact numbers are illustrative — your block number and balance will differ. `getBlockNumber()` and `getTransactionCount()` return a `number`, while `getBalance()` returns a `bigint` in wei (format it with `ethers.formatEther()`).
## Try it live
Run these read-only calls against Sei mainnet right now — no install, no private key. They're plain JSON-RPC, the same reads the script above performs.
## Edit and run
Edit and re-run the full ethers code from this page live in the browser — a real ethers v6 `JsonRpcProvider` reading Sei **testnet** (atlantic-2), so its block number and balances won't match the mainnet reads above:
## Browser Provider
In a browser context, connect to the user's injected wallet:
```ts theme={"dark"}
const provider = new ethers.BrowserProvider(window.ethereum);
const signer = await provider.getSigner();
const address = await signer.getAddress();
```
## Wallet from Private Key
For scripts and backend services:
```ts theme={"dark"}
const wallet = new ethers.Wallet('0xYourPrivateKey', provider);
```
## Sending a Transaction
Next step — this requires a funded account; get testnet SEI from the [faucet](/learn/faucet).
```ts theme={"dark"}
const tx = await wallet.sendTransaction({
to: '0xRecipient',
value: ethers.parseEther('1'),
});
const receipt = await tx.wait();
// receipt is final immediately — Sei has instant finality
```
## Reading a Contract
```ts theme={"dark"}
const abi = ['function balanceOf(address owner) view returns (uint256)'];
const contract = new ethers.Contract('0xTokenAddress', abi, provider);
const balance = await contract.balanceOf('0xYourAddress');
```
## Writing to a Contract
Pass a signer (wallet or browser signer) to the contract constructor for write operations:
```ts theme={"dark"}
const contract = new ethers.Contract('0xTokenAddress', abi, wallet);
const tx = await contract.transfer('0xRecipient', 1_000_000n);
const receipt = await tx.wait();
```
## Estimating Gas
```ts theme={"dark"}
const gas = await provider.estimateGas({
from: wallet.address,
to: '0xContractAddress',
data: '0xCalldata',
});
```
## Listening for Events
```ts theme={"dark"}
contract.on('Transfer', (from, to, value) => {
console.log('Transfer:', { from, to, value });
});
// Stop listening
contract.off('Transfer');
```
## Next Steps
* [Python quickstart (web3.py)](/evm/python-quickstart) — the same first steps in Python
* [ERC-20 interaction](/evm/evm-parity/examples/erc20) — full token read/write examples
* [ERC-721 interaction](/evm/evm-parity/examples/erc721) — NFT ownership, transfers, and approvals
* [Pointer contracts](/evm/evm-parity/examples/pointer-contracts) — interact with CosmWasm tokens via ERC interfaces
* [WebSocket connections](/evm/evm-parity/websocket) — real-time block and event subscriptions