> For the complete documentation index, see [llms.txt](https://docs.getblock.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.getblock.io/api-reference/zksync/eth_call-zksync.md).

# eth\_call - zkSync

Executes a read-only call against contract state without committing a transaction. Use it to query contract data through view/pure functions or to simulate state-changing calls without paying gas.

## Parameters

| Parameter      | Type   | Required | Description                                                                                  |
| -------------- | ------ | -------- | -------------------------------------------------------------------------------------------- |
| callObject     | object | Yes      | Transaction-shaped object with `to`, `data`, and optional `from`, `gas`, `gasPrice`, `value` |
| blockParameter | string | Yes      | Block number in hex, or block tag                                                            |

## Request Example

{% tabs %}
{% tab title="cURL" %}

```bash
curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_call",
    "params": [
        {
            "to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049",
            "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"
        },
        "latest"
    ],
    "id": "getblock.io"
}'
```

{% endtab %}

{% tab title="JavaScript (Axios)" %}

```javascript
import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "eth_call",
    "params": [
        {
            "to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049",
            "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"
        },
        "latest"
    ],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));
```

{% endtab %}

{% tab title="Python (Requests)" %}

```python
import requests
import json

url = "https://go.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "eth_call",
    "params": [
        {
            "to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049",
            "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"
        },
        "latest"
    ],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)
```

{% endtab %}

{% tab title="Rust (Reqwest)" %}

```rust
use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "eth_call",
        "params": [
                {
                        "to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049",
                        "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"
                },
                "latest"
        ],
        "id": "getblock.io"
});

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}
```

{% endtab %}
{% endtabs %}

## Response Example

{% code overflow="wrap" %}

```json
{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "0x0000000000000000000000000000000000000000000000056bc75e2d63100000"
}
```

{% endcode %}

## Response Parameters

| Field  | Type   | Description                                           |
| ------ | ------ | ----------------------------------------------------- |
| result | string | ABI-encoded return value of the called function (hex) |

## Use Cases

* Reading ERC-20 balances via `balanceOf`
* Querying DEX pool reserves and prices
* Simulating swaps and complex multi-call sequences
* Reading NFT ownership and metadata

## Error Handling

| Status Code | Error Message      | Cause                                                                  |
| ----------- | ------------------ | ---------------------------------------------------------------------- |
| 403         | Forbidden          | Missing or invalid `<ACCESS-TOKEN>`                                    |
| -32602      | Invalid params     | Request parameters are missing or malformed                            |
| 429         | Too Many Requests  | Rate limit exceeded for your plan                                      |
| -32000      | Execution reverted | The contract call reverted; check the data field for the revert reason |

## SDK Integration

{% tabs %}
{% tab title="zksync-ethers (JavaScript)" %}
{% code overflow="wrap" %}

```javascript
import { Provider } from 'zksync-ethers';

const provider = new Provider('https://go.getblock.io/<ACCESS-TOKEN>/');

// zksync-ethers exposes both standard Ethereum methods and zks_* methods
// through typed accessors. For raw access:
const result = await provider.send('eth_call', [{"to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049", "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"}, "latest"]);
console.log(result);
```

{% endcode %}
{% endtab %}

{% tab title="zksync2-python (Python)" %}

```python
from zksync2.module.module_builder import ZkSyncBuilder

zk_web3 = ZkSyncBuilder.build('https://go.getblock.io/<ACCESS-TOKEN>/')

# zksync2-python exposes the JSON-RPC layer directly.
result = zk_web3.zksync._zks_endpoints if 'eth_call'.startswith('zks_') else None
# Or call any method generically:
result = zk_web3.provider.make_request('eth_call', [{"to": "0x36615cf349d7f6344891b1e7ca7c72883f5dc049", "data": "0x70a08231000000000000000000000000d85498dbeaeb1df24be52eed4f52eac2fbd56245"}, "latest"])
print(result)
```

{% endtab %}
{% endtabs %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## 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, and the optional `goal` query parameter:

```
GET https://docs.getblock.io/api-reference/zksync/eth_call-zksync.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.
