# Return an entry from a map

{% code fullWidth="false" expandable="true" %}

```typescript
import { Cl, cvToHex } from "@stacks/transactions";

// Query a map entry from a contract
const contractAddress = "ST1PQHQKV0RJXZFY1DGX8MNSNYVE3VGZJSRTPGZGM";
const contractName = "my-contract";
const mapName = "user-balances";

// Create the map key (e.g., a principal)
const mapKey = Cl.standardPrincipal("ST1SJ3DTE5DN7X54YDH5D64R3BCB6A2AG2ZQ8YPD5");

const response = await fetch(
  `https://api.hiro.so/v2/map_entry/${contractAddress}/${contractName}/${mapName}`,
  {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
    },
    body: JSON.stringify(cvToHex(mapKey)),
  }
);

const result = await response.json();
const data = result.data ? Cl.deserialize(result.data) : null;

console.log("Map value:", data);
```

{% endcode %}

### Description

Query contract map data using the Stacks API map\_entry endpoint

### Use Cases

* Reading user balances from token contracts
* Checking NFT ownership records
* Retrieving configuration values from contracts
* Monitoring contract state without transactions

### Key Concepts

* **POST request** - Send the serialized map key
* **Hex encoding** - Keys must be hex-encoded Clarity values
* **Response format** - Returns hex-encoded Clarity value or null


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.stacks.co/cookbook/clarity/data-utility/return-an-entry-from-a-map.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.