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

# Field Types Reference

> All field types returned by the board schema endpoint and the value formats to use when reading or writing card data.

When you fetch the board schema, each field includes a `type` property. This type determines what value format the API expects when you create or update a card.

Always fetch the schema before writing to a board so you know the key and type for each field.

## Field types

### `text`

A plain text string.

```json theme={null}
{ "<fieldKey>": "123 Main Street" }
```

### `number`

A numeric value. Do not wrap in quotes.

```json theme={null}
{ "<fieldKey>": 3 }
```

### `money`

A numeric value representing a dollar amount. Do not include currency symbols or commas.

```json theme={null}
{ "<fieldKey>": 1850.00 }
```

### `date`

An ISO 8601 date string.

```json theme={null}
{ "<fieldKey>": "2025-09-01" }
```

### `datetime`

An ISO 8601 datetime string with timezone.

```json theme={null}
{ "<fieldKey>": "2025-09-01T10:00:00.000Z" }
```

### `boolean`

`true` or `false`.

```json theme={null}
{ "<fieldKey>": true }
```

### `select`

A single string value matching one of the field's configured options exactly. Option values are case-sensitive.

```json theme={null}
{ "<fieldKey>": "Active" }
```

### `multiselect`

An array of strings, each matching a configured option exactly.

```json theme={null}
{ "<fieldKey>": ["Dog", "Cat"] }
```

### `person`

A single contact ID string referencing a contact in your company.

```json theme={null}
{ "<fieldKey>": "<contactId>" }
```

### `persons`

An array of contact ID strings.

```json theme={null}
{ "<fieldKey>": ["<contactId1>", "<contactId2>"] }
```

### `email`

A valid email address string.

```json theme={null}
{ "<fieldKey>": "jane@example.com" }
```

### `phone`

A phone number string. Include country code for best compatibility.

```json theme={null}
{ "<fieldKey>": "+14155551234" }
```

### `url`

A fully qualified URL string.

```json theme={null}
{ "<fieldKey>": "https://example.com" }
```

### `file`

Files are attached via the [Upload a file to a card](/api-reference/cards/upload-a-file-to-a-card) endpoint, not via field keys in the card body.

## Reading field values

When you fetch a card, field values are returned using the same key/value structure. Null or unset fields are returned as `null`.

## Unknown types

If the schema returns a type not listed here, treat the value as a plain string and contact Aptly support to confirm the expected format.