--- title: Property types slug: cms-13/docs/built-in-property-types docTags: createdAt: 2026-07-30T20:22:06.232Z --- Optimizely Content Management System (CMS) content is built from models with properties that store and present data. Use many built-in property types in your models or create your own. Most property types work as instance or list properties. Some types are list types themselves; those cannot be modeled as lists. ## Common property types These property types cover the most frequent content modeling needs. | What you want to create | Property solution | Editing experience | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------- | ---------------------- | | **Plain short text** – Control the allowed length with the `StringLength` attribute. Use a custom tag to control the containing tag, such as using an H1 for the main header for the page. | `String` | One row input | | **Plain long text** – Control the allowed length with the `StringLength` attribute. | `String` with `UIHint.Textarea` | Text area | | **HTML** | `XHtmlString` | A TinyMCE HTML editor | | **Integer value** – Controls other rendering, such as the number of items in a list. Control the min and max values with the `Range` attribute. | `Int` | A number slider | | **Date and time** – Control the min and max values with the `Range` attribute. | `DateTime` | A date and time picker | | **Double** – Control the min and max values with the `Range` attribute. | `Double` | Check editor | | **Boolean** | `Boolean` | Checkbox | | **Page type** – Filter items in a list, and so on. | `PageType` | | | **BLOB** – Hold binary data (such as an image). Route to a BLOB with pattern `/BlobPropertyName`. | `Blob` | | ## Work with other content Reference existing content with `Link` or `LinkCollection` to create internal or external links. - `ContentArea` displays content from other content items. - `ContentReference`, `ContentReferenceList`, or `URL` link to a single content item of a specified type. - The `AllowedTypes` attribute further restricts the kind of links that can be added to a property (although there are a few known limitations). ## `ContentReference` property type `ContentReference` is a built-in property type that references a single content item of a specified type. ```csharp [AllowedTypes(typeof(MyPageType))] public virtual ContentReference FeaturedPage { get; set; } ``` :::hint{type="info"} **Note** `PageReference` is now obsolete. Always use `ContentReference` for pages, media, or blocks. ::: Use a content reference with many UI hints to select different entities in CMS, such as a block, a media item, a block folder, or a media folder. | What you want to create | Property solution | Editing experience | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------- | ------------------------------------------------- | | *Link to a media file of any type* – Link to any file in the media repository. Use `ContentReference` instead to use standard content rendering. (Mostly for backward compatibility.) | `ContentReference` with `UIHint.MediaFile` | Content picker with drag and drop support | | *Link to an image* – Lets an editor select content in the media repository by implementing IContentImage. | `ContentReference` with `UIHint.Image` | Content picker with drag and drop support | | *Link to a video* – Lets an editor select content in the media repository by implementing `IContentVideo`. | `ContentReference` with `UIHint.Video` | Content picker with drag and drop support | | *Link to a media file* with the possibility to append information in the URL – Each link can be an item inside Optimizely CMS, such as pages, media, and external URLs. Use URL instead of `ContentReference` to add information, such as query string parameters to control size. | `Url` with `UIHint.MediaFile` or `UIHint.Image` or `UIHint.Video` | Content picker with drag and drop support | | **Content area** | `ContentArea` | | | **URL** | `Url` | Link dialog with drag-and-drop support | | Link to multiple external and/or internal resources – Does not support `AllowedTypesAttribute`. | `LinkItemCollection` | Link collection editor with drag-and-drop support | | *Link to external or internal resource* – Does not support `AllowedTypesAttribute`. | `LinkItem` *Note:* Available in CMS 12.11.0 and later. | Link editor with drag-and-drop support | | *Link to multiple internal pages, media files, or other content types* – Supports `AllowedTypesAttribute`. | `ContentReferenceList` | Content picker with drag and drop support | ## Select predefined values Give editors a constrained set of choices with drop-down and checkbox list properties. | What you want to create | Property solution | Editing experience | | -------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ---------------------------- | | Select a single item from a relatively short list of options | `String/Int` with [SelectOne](docId\:YdQ7XJVCyExSpREs6UZdU) attribute | Link to implementation page | | Select several items from a relatively short list of options | `String/Int` with [SelectMany](docId\:YdQ7XJVCyExSpREs6UZdU) attribute | Link to implementation page | | Select a single item from a relatively long list of options. – Use with caution because the auto-suggestion editor creates requests to the server. | `String/Int` with [AutoSuggestion](docId\:h4HllBw63IQIo0AAJmw1g) attribute | Link to implementation page | ## Validation attributes Validation attributes enforce data constraints on content properties. CMS supports the following .NET validation attributes: - `Range` - `StringLength` - `RegularExpression` - `EmailAttribute` Create custom attributes that implement `ValidationAttribute`. See [Write custom attributes](docId\:Lf16CF5ko_Z1L0Og1ENvf).