> For the complete documentation index, see [llms.txt](https://docs.overflowcms.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.overflowcms.com/api-reference/field-types-and-data-shapes.md).

# Field Types & Data Shapes

## Field Types & Data Shapes

What each field type actually serializes to in the `data` object of a published item.

| Type        | JSON shape                  | Example                                                                                                       |
| ----------- | --------------------------- | ------------------------------------------------------------------------------------------------------------- |
| `text`      | `string`                    | `"Shipping unlimited items on Webflow"`                                                                       |
| `richText`  | `string` (HTML)             | `"<p>Webflow's CMS caps you at 100 items...</p>"`                                                             |
| `image`     | MediaRef object             | `{ "mediaId": "...", "url": "...", "srcset": "...", "alt": "...", "width": 1280, "height": 720 }`             |
| `video`     | MediaRef object             | Same shape as `image`.                                                                                        |
| `number`    | `number`                    | `4.5`                                                                                                         |
| `date`      | ISO-8601 `string`           | `"2026-07-12T00:00:00.000Z"`                                                                                  |
| `boolean`   | `boolean`                   | `true`                                                                                                        |
| `option`    | `string`                    | One of the values you defined for that field, e.g. `"news"`                                                   |
| `reference` | Resolved object (one level) | The referenced item's own `data`, nested under the field's key — not just a bare id, once resolved by the API |

### MediaRef

```ts
interface MediaRef {
  mediaId: string;
  url?: string;
  srcset?: string;
  alt?: string;
  width?: number;
  height?: number;
}
```

`srcset` is only present when the image pipeline generated responsive variants (Cloudflare Images) — an externally-pasted image URL may only carry `url`.

### Which types are indexable

Only indexed values can be used in `sort`/`filter` (see Collections & Items):

| Type        | Indexable | Index kind |
| ----------- | --------- | ---------- |
| `text`      | Yes       | text       |
| `number`    | Yes       | numeric    |
| `date`      | Yes       | numeric    |
| `boolean`   | Yes       | numeric    |
| `option`    | Yes       | text       |
| `reference` | Yes       | text       |
| `richText`  | No        | —          |
| `image`     | No        | —          |
| `video`     | No        | —          |

### Plan gates

`reference` and `video` fields require the **Pro** plan or above — they're hidden/disabled in the field-type picker below that tier. See Plans & Billing.


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