> ## Documentation Index
> Fetch the complete documentation index at: https://companyname-a7d5b98e-cookbook-ton-center.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Monitor a Wallet

> Learn how to continuously watch a wallet for new transactions and balance updates using Ton Center APIs.

This guide shows how to create a **wallet monitor** using the Ton Center API.\
It continuously polls the blockchain for the latest transaction and balance of a given wallet address, and alerts when new transactions are detected.

This recipe is useful for:

* Building bots that notify users of incoming/outgoing payments
* Tracking balances for custodial or exchange wallets
* Exploring and debugging account activity in real time

<Info>
  The examples use the public Ton Center endpoint:

  ```
  https://toncenter.com/api/v2/jsonRPC
  ```

  For production, you should request your own API key and use a dedicated endpoint for higher rate limits and stability.
</Info>

***

## 1. Fetching transactions

Transactions for an account can be retrieved via the `getTransactions` method.

Example request:

```bash theme={null}
curl -X POST https://toncenter.com/api/v2/jsonRPC \
  -H "Content-Type: application/json" \
  -d '{
    "id": 1,
    "jsonrpc": "2.0",
    "method": "getTransactions",
    "params": [{ "address": "EQDtFpEwcFAEcRe5mLVh2N6C0x-_hJEM7W61_JLnSF74p4q2", "limit": 1 }]
  }'
```

***

## 2. Checking balance

To query the balance of an account, use the `getAddressBalance` method.

Example request:

```bash theme={null}
curl -X POST https://toncenter.com/api/v2/jsonRPC \
  -H "Content-Type: application/json" \
  -d '{
    "id": 1,
    "jsonrpc": "2.0",
    "method": "getAddressBalance",
    "params": ["EQDtFpEwcFAEcRe5mLVh2N6C0x-_hJEM7W61_JLnSF74p4q2"]
  }'
```

***

## 3. Code Implementation

The script polls every 5 seconds and prints balance updates and new transactions.

<Tabs>
  <Tab title="JavaScript (@ton/core)">
    Install dependencies:

    ```bash theme={null}
    yarn add ton ton-crypto ton-core buffer
    ```

    Code:

    ```js theme={null}
    import { TonClient, Address } from "ton";

    const client = new TonClient({
      endpoint: "https://toncenter.com/api/v2/jsonRPC",
    });

    const address = Address.parse(
      "EQDtFpEwcFAEcRe5mLVh2N6C0x-_hJEM7W61_JLnSF74p4q2"
    );

    let lastSeenLt = null;

    async function checkTransactions() {
      try {
        const txs = await client.getTransactions(address, { limit: 1 });
        const latest = txs[0];

        if (latest) {
          if (lastSeenLt && latest.lt !== lastSeenLt) {
            console.log("  New transaction detected!");
            console.log("  lt:", latest.lt, "hash:", latest.hash().toString("base64"));
          }
          lastSeenLt = latest.lt;
        }

        const balance = await client.getBalance(address);
        console.log("Current balance:", balance.toString(), "nanotons");
      } catch (err) {
        console.error("Error:", err.message);
      }
    }

    setInterval(checkTransactions, 5000);

    console.log("Monitoring transactions for", address.toString());
    ```

    Output example:

    ```bash theme={null}
    Monitoring transactions for EQDtFpEwcFAEcRe5mLVh2N6C0x-_hJEM7W61_JLnSF74p4q2
    Current balance: 1317379090350631577 nanotons
      New transaction detected!
      lt: 61948272000003n
    hash: LrWzfCoHKUSHK9RqgznOuZ841KG3eyEeo3uZbcy/Hzs=
    Current balance: 1317379090350537050 nanotons
    ```
  </Tab>
</Tabs>

***

## 4. Use Cases

* **Notification bots** – Send Telegram/Discord alerts when a user’s wallet receives or spends TON.
* **Custodial wallets** – Exchanges or custodians can track balances in real time for hot wallets.
* **Developer debugging** – Easily follow transaction activity while testing dApps or smart contracts.