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Technical specification of ad formats


This is a completely full-fledged HTML fragment that will be inserted into the page in an iframe tag


Required file type

Banners in HTML5 format must be delivered as a separate archive with the ZIP extension.

Naming of the ZIP archive

For easy manipulation with banners in HTML5 format, name each ZIP archive as follows: Client + Action + HTML5 + banner size / name (eg: This will significantly speed up the entire process of deploying a banner in the advertising system.

Banner structure

The HTML5 banner archive (ZIP) must contain a startup file with the extension ".html" and any other files that are necessary for the error-free display of the banner on the page. All files and directories must be stored in the first level of the archive, ie without folders and subfolders

Supported file types

V rámci archivu banneru HTML5 (ZIP) jsou povoleny všechny níže vyjmenované typy souborů:

  • CSS
  • JS
  • HTML
  • JSON
  • GIF
  • PNG
  • JPG
  • SVG
  • EOT
  • XML

Number and names of files

  • The number of all files in the HTML5 banner archive must not exceed 40.
  • File names in the archive must not contain accents or special characters. If the banner is generated by an external program (Adobe Edge Animate, Google Webdesigner), it is necessary to make sure that the layer names do not contain accents or special characters before exporting the banner.

Loading data from external sources

The total maximum banner data size, including all scripts, libraries, and external service data sources that are downloaded after placement on a page, should not exceed 1MB when unpacked. We strongly recommend using external sources from fast and reliable CDNs to eliminate errors due to slow CDN responses. We reserve the right to reject if the 1 MB limit is exceeded.

Recommended external sources:


When loading support libraries, the script address must start with two slashes (see example below).

Correct: <script src="//"></script>
Incorrect: <script src=""></script>

Click-thru settings

Within the HTML5 banner, redirection to only one URL is supported, which must be sent together with the banner separately. The entire clickable portion of the banner (<a> element with href attribute, no onclick ). Our ad system sets the destination address in the href attribute. Use of JavaScript (eg (); ) is not allowed.

Proper functionality

Caution! The manufacturer is responsible for the correct display and trouble-free functionality in all major browsers, including mobile versions.


  1. There can be only one ".html" file in the banner archive.
  2. No redirects (or other address changes) may occur inside the iframe, causing that a click on the browser's Back button on our page could not take you to the previous page.
  3. The clickable part of the banner must have a standard cursor when hovering over the links. Over non-clickable parts must be a normal cursor.
  4. The banner must not steal focus or cause us to leave our site without standard explicit user action (i.e. not without mouse click, enter key or touch which started and ended at the same point).
  5. The banner must not emit sounds without mouse hovering over the ad or without explicit user action.
  6. Some users use a different default font size. We don't require the banner to look the same in all sizes, we just point out that it's important not to forget this flexibility of the environment (it can't be avoided).
  7. The supplied banner or creative must not overload the processor and use the memory resources of the device on which it is displayed. The evaluation is based on the iAB recommendation that individual creatives should not require more than 30% of available CPU resources (relative to the average user base). We reserve the right to reject the creative in the event of excessive workload and use of system resources.