---
url: /process-functions/mapping-exists.md
description: Checks whether a mapping exists.
---

# mapping.exists

Checks whether a mapping exists.

```js
mapping.exists(mappingName)
```

## Parameters

| Parameter | Type | Description |
|---|---|---|
| `mappingName` | `string` | The mapping's name or id. |

## Returns

`true` if the mapping exists, otherwise `false`.

## Examples

```js
if (mapping.exists("Time to Year and Month")) {
    // it exists
}
```

## Related

* [mapping.create](/process-functions/mapping-create)
* [mapping.delete](/process-functions/mapping-delete)