The Adzerk Developer Hub

Welcome to the Adzerk developer hub. You'll find comprehensive guides and documentation to help you start working with Adzerk as quickly as possible, as well as support if you get stuck. Let's jump right in!

Creatives General Settings


This section covers the settings of a creative.

In Adzerk lingo, creative refers to details about the ad itself (such as its format, the image file, size, URL, and metadata). This is different from our ad terminology, which refers to a specific creative that's tied to a flight and ready to serve. They are broken apart because an ad includes both the creative details and ad-level targeting details. The creative can live at the Advertiser level, while ad lives under Flights.

If a creative is set to inactive, then all ads (creatives mapped to a flight) are not able to serve even if they are set to active. Make sure creatives AND ads are active before your campaign goes live.

General Settings

Format - The file format of the ad, with the below options.

Image/Flash (.gif/.jpg/.png/swf) or Audio File (.mp3, .wav) - If chosen, you'll have option to 'Choose File' and upload one, or load an image by putting its URL in the File URL box.

The max file size is 1MB

If you choose Audio File, choose the Ad Size you will use for the audio ad's placement.

Javascript/HTML - If chosen, add the code.

Optional: Use the "Convert to Adzerk Macros" button to automatically insert macros to tags supported in our Third Party Clicking Tracking article (a beta feature).

Custom Template - If chosen, choose from the selected Template you've already created.

Creative Templates are a BETA feature. See here for more info.

Friendly Name - This is the name you want to give the creative

Ad Size - Choose between the options. More info about Ad Sizes & Types can be found here.

Click URL & Alt Text- The URL and URL Alt Text you want to use when someone clicks on the ad.

The max length for a Click URL is 2000 characters.

Use http://, https://, or // if you want to dynamically select the correct protocol. The Alt Text field should have screen reader friendly text.

Validation - A checkbox sets whether the image you upload is validated. The validation checks whether:

  • The dimensions of the file match the dimensions of the Ad Size
  • The file has one of the supported file extensions

By default, this checkbox is checked. You can uncheck to override the validation.

Metadata Field

The Metadata field (which is called customData in the Decision API Response) is a powerful tool that spits out additional information tied to the ad. When you request an ad, any metadata associated with it will be returned in the ad response.

For instance, you could include data about a "call-to-action", then take the corresponding text in the Decision API response and insert that into your ad.

  "headline": "Test Headline",
  "cta": "Download Here"

In the above example, the Decision API Response, alongside the tracking URLs and ad image and other parameters, will return this metadata, which you can use how you'd like.

A maximum of 1000 characters is allowed in the Metadata JSON object.

Metadata must be formatted as a JSON object. And when uploading via the API, you must urlencode the entire Metadata string to support URLs and special characters that can break the JSON object. For instance: { ... "Metadata": "{ \"foo\":1234 }" }

Setting up Metadata in UI

In the Create/Edit Ad section, add the Metadata in JSON format in the Metadata box.

Setting up Metadata in API

When using the Create Creatives endpoint, include the JSON string in the metadata field.

Required Fields For Creatives in the UI

Field Name
Required for JS/HTML Creatives
Required for Image Creatives

Any JS or HTML (unless the empty creative override checkbox is checked)



Friendly Name



Ad Size



Click URL



Image Upload OR File URL



Mapping UI and API Fields

Below is a mapping of the fields from the UI and the Create Creative endpoint.


Friendly Name


Ad Size


Click URL


Alt Text



Metadata in the Create Creatives Endpoint. CustomData in the Decision API Response

JavaScript/HTML Format


JavaScript/HTML code

ScriptBody in the Create Creatives Endpoint. Body in the Decision API Response

File URL


Image file/Choose File

Use Upload Creative Image endpoint