*REST API › Objects › Platform*

# Custom field definition

> DEFINITION of a custom field of the account: its identifier, the type it admits and the values it accepts.

The definition of a custom field of the account: its identifier, the type of data it admits, the values it accepts if it is a dropdown, and the kind of entity it applies to. It is not the value stored on any record; values travel inside each resource. Read the definitions before you write a custom field. Custom fields use the tenancy inherited from the parent account.

Schemas: `CustomFieldDefinitionDto`

## Attributes

| Name | Type | Description |
| --- | --- | --- |
| `id` | string | Unique identifier of the definition. It is the one used when writing a value. |
| `name` | string | Display name of the field. |
| `dataType` | string | Data type the field accepts. `text`, `multitext`, `dropdown`, `checkbox`, `radio`, `date`, `contact`, `item`, `space`, `staff_member`, `vehicle` |
| `description` | string | Field description; null if it has none. |
| `options` | string[] | Allowed values when the field is a dropdown. Empty for the other types. |
| `applyAt` | string[] | Entities the field can be used on. `order`, `item`, `space`, `contact`, `project`, `kit`, `orderTemplate`, `repairTicket`, `serializedItem`, `vehicle`, `staff`, `service`, `purchaseOrder`, `incident`, `opportunity`, `document`, `all` |
| `showOn` | string[] | Documents the field is printed on. `quote`, `proforma`, `invoice`, `contract`, `packing_slip`, `purchase_order`, `repair_ticket`, `all` |
| `isActive` | boolean | true if the definition is active and can be used. |
| `createdAt` | string<date-time> | Creation date in ISO 8601 UTC; null if not recorded. |
| `updatedAt` | string<date-time> | Last modification date in ISO 8601 UTC; null if not recorded. |

## Values

| Field | Values |
| --- | --- |
| `dataType` | `text`, `multitext`, `dropdown`, `checkbox`, `radio`, `date`, `contact`, `item`, `space`, `staff_member`, `vehicle` |
| `applyAt` | `order`, `item`, `space`, `contact`, `project`, `kit`, `orderTemplate`, `repairTicket`, `serializedItem`, `vehicle`, `staff`, `service`, `purchaseOrder`, `incident`, `opportunity`, `document`, `all` |
| `showOn` | `quote`, `proforma`, `invoice`, `contract`, `packing_slip`, `purchase_order`, `repair_ticket`, `all` |

## Example

*Custom field definition · Generated from the schema*

```json
{
  "id": "id_8f2a1c",
  "name": "Example",
  "dataType": "text",
  "description": "string",
  "options": [
    "string"
  ],
  "applyAt": [
    "order"
  ],
  "showOn": [
    "quote"
  ],
  "isActive": true,
  "createdAt": "2026-09-01T08:00:00Z",
  "updatedAt": "2026-09-01T08:00:00Z"
}
```

## Returned by

- [`GET /api/v1/custom-fields`](https://docs.filmo.io/rest-api/endpoint-reference/custom-fields/list-custom-field-definitions) — List custom field definitions

## Modified by

No operation.

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Canonical URL: https://docs.filmo.io/rest-api/objects/custom-field-definition  
Last updated: 2026-10-25