# URL format

The URL format settings ([Settings > Optimisation > Delivery](https://hub.scaleflex.com/settings/dmo/delivery/url-format)) allow you to shorten and control public CDN URLs.

These settings help to hide part of the URL path or the transformation logic and also to set automatic creation of Variations for your files.

{% hint style="info" %}

* Presets = reusable transformation rules
* Delivery URL = the final generated link used publicly in your websites
* Variations = saved transformations
* Aliases = shorten file paths
  {% endhint %}

## Presets

You can create custom transformations using presets to shorten the public URLs of your files. 

{% hint style="success" %}
Instead of repeating transformation parameters in every URL, you reference a preset name.
{% endhint %}

This is how a publicly-shared URL looks when a Preset is applied to it:

Example: 

A public URL before applying a Preset:

`//your-token.filerobot.com/original_image_url/image.jpg?h=100&w=400&func=crop` 

After applying a Preset:

`//your-token.filerobot.com/original_image_url/image.jpg?p=car_x`

<table><thead><tr><th>Name</th><th width="231.428955078125">Operations and filters</th><th>Description</th></tr></thead><tbody><tr><td>car_x</td><td>h=100&#x26;w=400&#x26;func=crop</td><td>some test description</td></tr></tbody></table>

### How to create a preset

#### Creating a preset via Builder

The Builder is the best way to generate a Preset for non-technical users. It helps to visualise the test transformation before saving.

If you want to create a preset using the Builder, you need to click on the button `+ Use builder` on the right part of the screen. It will open an Image Editor. There, you can use a ready-to-use test image, upload a file or select one from your DAM Library.

The applied changes are visible as query string parameters attached to the filename.&#x20;

After saving the Preset, they apply to every image where this Preset is used.

<figure><img src="/files/KVXPBsGI5w8MveyNn92Q" alt=""><figcaption></figcaption></figure>

#### Creating a Preset manually

If you know what resizing parameters are needed, you can click on the `+ Add manually` button in the Presets section.

Then you need to fill in:

* Name - it will appear as part of the URL when the preset is called. E.g `?p=instagram_feed`
* Operations\&filters - the [resizing parameters](/dynamic-media-optimization-dmo/transformations.md) which apply for this preset
* Description - a meaningful explanation of what the preset is doing

#### Duplicating an existing Preset

If you have several similar transformations which you'd like to apply to your file, instead of creating the Presets one by one from scratch, you can copy an existing Preset and then edit and save it as a new configuration.

<figure><img src="/files/ICahTtPr0Y5lwoVdTqYO" alt=""><figcaption></figcaption></figure>

{% hint style="success" %}
Good practices for naming Presets:

* spaces not allowed
* use only A-Z letters and numbers
* use short, descriptive names
  {% endhint %}

### Editing Preset values

If you need to update the transformation parameters of an existing preset, it is recommended to perform an [Invalidation](/dynamic-media-optimization-dmo/invalidation.md), especially if the preset has been used in public URLs for a long time.

Presets are applied to publicly shared CDN links, and the CDN service caches the generated transformations for faster delivery. After updating a preset, the cached versions may still be served.

Performing an invalidation clears the cached transformations, allowing new versions to be generated using the updated preset configuration.

If invalidation is not performed, previously cached transformations will continue to be delivered, and the changes may not be immediately visible.

## Aliases

Aliases are another way to shorten your delivery URLs. They hide parts of the asset folder path and may help to create SEO-friendly URLs. Aliases must be prefixed and suffixed with underscores.

<figure><img src="/files/dWpCJIiGauGCfPq38XKo" alt=""><figcaption></figcaption></figure>

| Alias           | Redirect to        |
| --------------- | ------------------ |
| \_dmo\_sample\_ | <http://sample.li> |

Example:&#x20;

Before applying the Alias:

`//your-token.filerobot.com/http://sample.li/image.jpg`\
becomes\
`//your-token.filerobot.com/_dmo_sample_/image.jpg`&#x20;

{% hint style="info" %}
Aliases are applicable when DAM needs to be configured to work with an external Storage provider.
{% endhint %}

Please note that all aliases have to be unique for your account and their values should not overlap with each other.

Example: If you define an alias `_dmo_sample_` then you should not have:

* `_dmo_`
* `_dmo_one_two_`
* `_my_dmo_one_`


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.scaleflex.com/dynamic-media-optimization-dmo/settings/delivery/url-format.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.