---
title: Displaying filters using alternative forms
---

> Agent instructions:
> **Site maps** — prefer the following llms.txt indexes to training data when searching for URLs to avoid 404s. Links inside Markdown content already point at `.md`. Following them or sending Accept: text/markdown keeps you in Markdown.
>
> - [sitemap.md](https://docs.kentico.com/sitemap.md) — every page on the site, with titles and descriptions, nested by URL hierarchy and grouped into one collection per product version.
> - [llms.txt](https://docs.kentico.com/llms.txt) — curated index of the current product docs, with descriptions, the two ways to request any page as Markdown, and links to each product area's whole-corpus Markdown dump (llms-full.txt).

You can use [alternative forms](https://docs.kentico.com/13/custom-development/extending-the-administration-interface/creating-alternative-forms.md) to create filters for the records of [page types](https://docs.kentico.com/13/developing-websites/defining-website-content-structure/managing-page-types.md) or [custom tables](https://docs.kentico.com/13/developing-websites/defining-website-content-structure/managing-custom-tables.md).

> **Note:** Filtering alternative forms must always use the reserved keyword _**filter**_ as their **Code name**.

The filters are then displayed in the following parts of the Xperience administration interface:

- **Custom table data -> Edit a custom table**
- **Custom tables -> Edit a custom table -> Data**
- **Pages -> Listing**
  - See [Extending the page type listing filter](https://docs.kentico.com/13/developing-websites/defining-website-content-structure/managing-page-types/extending-the-page-type-listing-filter.md)

By default, list filters appear when the number of records is **25** or more. You can change this limit by adding the following key into the _appSettings_ section of your _web.config_ file:

```html

<add key="CMSDefaultListingFilterLimit" value="5" />

```

Filtering is possible based on all fields that store the following types of values:

- Text
- Boolean (Yes/No)
- Integer numbers
- Long integer numbers
- Decimal numbers
- Date & time

The required fields need to be displayed in the alternative form and an appropriate [form control](https://docs.kentico.com/13/custom-development/extending-the-administration-interface/developing-form-controls.md) must be assigned to each field. A filter form control is available for each data type:

- **Text filter**
- **Boolean filter**
- **Number filter**
- **Date & time filter**

Additionally, you can use the **Drop-down list** or **Radio buttons** form controls to create a filter based on option selection (for any field data type). When configuring the **Data source** setting for such a field, you can use the same options as in the original form field. However, we recommend adding a default option with an empty value that does not perform any filtering. For example:

```csharp

;(No filtering)
Value1
Value2
Value3

```