# mac

> This document is the Markdown version of [valibot.dev/api/mac/](https://valibot.dev/api/mac/). For the complete documentation index, see [llms.txt](https://valibot.dev/llms.txt).

Creates a [MAC address](https://en.wikipedia.org/wiki/MAC_address) validation action.

> This validation action accepts 48-bit and 64-bit MAC addresses. For a more specific validation, you can also use [`mac48`](/api/mac48.md) or [`mac64`](/api/mac64.md).

```ts
const Action = v.mac<TInput, TMessage>(message);
```

## Generics

- `TInput` `extends string`
- `TMessage` `extends ErrorMessage<MacIssue<TInput>> | undefined`

## Parameters

- `message` `TMessage`

### Explanation

With `mac` you can validate the formatting of a string. If the input is not a MAC address, you can use `message` to customize the error message.

## Returns

- `Action` `MacAction<TInput, TMessage>`

## Examples

The following examples show how `mac` can be used.

### MAC schema

Schema to validate a MAC address.

```ts
const MacSchema = v.pipe(
  v.string(),
  v.mac('The MAC address is badly formatted.')
);
```

## Related

The following APIs can be combined with `mac`.

### Schemas

[`any`](/api/any.md), [`custom`](/api/custom.md), [`string`](/api/string.md)

### Methods

[`pipe`](/api/pipe.md)

### Utils

[`isOfKind`](/api/isOfKind.md), [`isOfType`](/api/isOfType.md)