> ## Documentation Index
> Fetch the complete documentation index at: https://axiom.co/docs/llms.txt
> Use this file to discover all available pages before exploring further.

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://axiom.co/docs/feedback

```json
{
  "path": "/apl/scalar-functions/ip-functions/parse-ipv4-mask",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# parse_ipv4_mask

> This page explains how to use the parse_ipv4_mask function in APL.

## Introduction

The `parse_ipv4_mask` function in APL converts an IPv4 address and its associated netmask into a signed 64-bit wide, long number representation in big-endian order. Use this function when you need to process or compare IPv4 addresses efficiently as numerical values, such as for IP range filtering, subnet calculations, or network analysis.

This function is particularly useful in scenarios where you need a compact and precise way to represent IP addresses and their masks for further aggregation or filtering.

## For users of other query languages

If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.

<AccordionGroup>
  <Accordion title="Splunk SPL users">
    In Splunk SPL, you use functions like `cidrmatch` for subnet operations. In APL, `parse_ipv4_mask` focuses on converting an IP and mask into a numerical representation for low-level processing.

    <CodeGroup>
      ```sql Splunk example theme={null}
      | eval converted_ip = cidrmatch("192.168.1.0/24", ip)
      ```

      ```kusto APL equivalent theme={null}
      print converted_ip = parse_ipv4_mask("192.168.1.0", 24)
      ```
    </CodeGroup>
  </Accordion>

  <Accordion title="ANSI SQL users">
    In ANSI SQL, you typically use custom expressions or stored procedures to perform similar IP address transformations. In APL, `parse_ipv4_mask` offers a built-in, optimized function for this task.

    <CodeGroup>
      ```sql SQL example theme={null}
      SELECT inet_aton('192.168.1.0') & (0xFFFFFFFF << (32 - 24)) AS converted_ip
      ```

      ```kusto APL equivalent theme={null}
      print converted_ip = parse_ipv4_mask("192.168.1.0", 24)
      ```
    </CodeGroup>
  </Accordion>
</AccordionGroup>

## Usage

### Syntax

```kusto theme={null}
parse_ipv4_mask(ip, prefix)
```

### Parameters

| Name     | Type   | Description                                                               |
| -------- | ------ | ------------------------------------------------------------------------- |
| `ip`     | string | The IPv4 address to convert to a long number.                             |
| `prefix` | int    | An integer from 0 to 32 representing the number of most-significant bits. |

### Returns

* A signed, 64-bit long number in big-endian order if the conversion is successful.
* `null` if the conversion is unsuccessful.

### Example

```kusto theme={null}
print parse_ipv4_mask("127.0.0.1", 24)
```

## Use case example

Use `parse_ipv4_mask` to analyze logs and filter entries based on IP ranges.

**Query**

```kusto theme={null}
['sample-http-logs']
| extend masked_ip = parse_ipv4_mask('192.168.0.1', 24)
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B'sample-http-logs'%5D%20%7C%20extend%20masked_ip%20%3D%20parse_ipv4_mask\('192.168.0.1'%2C%2024\)%22%7D)

**Output**

| \_time              | uri         | method | masked\_ip    |
| ------------------- | ----------- | ------ | ------------- |
| 2024-11-14T10:00:00 | /index.html | GET    | 3,232,235,520 |

## List of related functions

* [ipv4\_compare](/apl/scalar-functions/ip-functions/ipv4-compare): Compares two IPv4 addresses lexicographically. Use for sorting or range evaluations.
* [ipv4\_is\_in\_range](/apl/scalar-functions/ip-functions/ipv4-is-in-range): Checks if an IP address is within a specified range.
* [parse\_ipv4](/apl/scalar-functions/ip-functions/parse-ipv4): Converts a dotted-decimal IP address into a numeric representation.