Technical specifications

The file type

HTML5 banners must be delivered as a standalone .ZIP archive.

Banner structure

HTML5 banner archive (.ZIP) must contain a main file with the extension ".html" (ex.: index.html) and any other files, that are necessary for a faultless display of the banner. All files and directories have to be stored in the root of the archive.

Supported file types

The allowed files in HTML5 banner archive (ZIP) are listed below:

  • CSS
  • JS
  • HTML
  • GIF
  • PNG
  • JPG
  • SVG
  • WOFF
  • TTF
  • EOT

Number of files

The number of files in the HTML5 banner archive must not exceed 20.

Data size

The total data size of HTML5 banner is determined by the size of all the files after packing into a ZIP archive.

Loading data from external sources

Additional loading of data from external sources is not allowed. Excluding supporting libraries stored on CDN (Adobe Edge Animate, Google Webdesigner).

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

Correct: <script src="//cdn.example.com/file.js"></script>
Wrong: <script src="http://cdn.example.com/file.js"></script>

Setting a click-through

There is only one URL allowed for redirecting from an HTML5 banner. The click-through needs to be implemented in compliance to the adserver's requirements (in order to make sure the platform responsible for managing the campaing is monitoring click-throughs).

Click-through example

Adform documentation
Specifications may be different for each adserver.

Correct functionality of banner

Warning! For correct display in different browsers corresponds to the manufacturer, who must ensure trouble-free operation in all major browsers, including mobile versions.


  1. There can only be one file with the ".html" extension in the banner archive.
  2. Filenames in the banner archive must not contain special and accented characters. If the banner is generated by an external application (Adobe Edge Animate, Google Webdesigner), it is necesarry to make sure there are no special or accented characters present in the layer names before exporting the banner.
  3. Animated HTML5 banners must not use too much of the user's system resources. If the advertisement is using too many system resources, browsers may automatically block it and won't display it.