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

# Update a contact custom field

> Change a custom field's name, type or position.

Every plan can use this endpoint. Send at least one field.

## Path Parameters

**fieldId** `string` *required*

Custom field UUID

## Body

**name** `string`

The new name, 1 to 255 characters after trimming.

**type** `string`

One of `text`, `number`, `date` or `boolean`.

**position** `integer`

Where the field sits in the list, a whole number from 0 up.

```bash cURL theme={null}
curl -X PATCH "https://api.nedzo.ai/v1/contacts/custom-fields/5c1d2e3f-4a5b-4c6d-8e7f-9a0b1c2d3e4f" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "position": 2 }'
```

```json Response theme={null}
{ "id": "5c1d2e3f-4a5b-4c6d-8e7f-9a0b1c2d3e4f", "workspaceId": "789e4567-e89b-12d3-a456-426614174000", "name": "Lead Source", "type": "text", "position": 2, "createdAt": "2026-10-11T12:00:00Z", "updatedAt": "2026-10-12T09:00:00Z" }
```

## Errors

| Status | When |
| - | - |
| `400` | `fieldId` is not a UUID, the body is empty (`Nothing to update`), or a field breaks its limit. |
| `404` | No custom field has this id, or it is not in this key's scope. |


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