Dynamic HTML banner

A non-interactive banner format which supports changing its content by the advertiser without re-approval while the ad is running.

The dynamic HTML banner is an HTML template with specific graphics. Banner content is defined using an XML file located on the client's server.

XML validity is verified by the Seznam.cz advertising system, which also takes care of updating the banner at the specified time interval (10 minutes by default). If the banner definition in the XML file does not match the template, the last correct banner or last correct XML is used.

Typically, this form of advertising is ideal for online shops promoting products, where the client wants to make immediate changes to their running ads.

It is not possible to display erotic advertising (i.e. erotic underwear, medication, etc.) through the dynamic HTML banner.

Example of dynamic HTML banner

Important information for running dynamic ads

In order to have a dynamic ad published, the client has to send the resources listed at least five days prior to launching the campaign:

  1. Preview of the dynamic banner
    Static HTML banner code together with static images, which do not change dynamically (logo, banner background, etc.).
  2. Description of static and dynamic parts of the dynamic banner (template)
    A specification of the parts that will change according to the XML file (pictures, texts, URL, etc.). Description must comply with the template rules listed below.
  3. URL from which XML will be downloaded
    The XML file, which will subsequently be downloaded, will be placed on this URL (created in compliance with the specifications listed below).

Technical specifications


List of permitted mime-types

  • text__plain – plain text
  • text__html – HTML code
  • image__gif – GIF image
  • image__jpeg – JPG image
  • image__png – PNG image

Design requirements

Text creatives

Maximum number of characters for each creative must be stated in the documentation.

Graphic creatives

The documentation must state if the image creatives should have a fixed or a variable size up to a given size limit (and its value in px) and the maximum data size in kB.

HTML creatives

  1. HTML code must not alter the parent site's design in any way. If present, the JavaScript code must not cause any errors.
  2. HTML creative must be sized accordingly to the type of the ad and its position.


Cascade style sheets (CSS) must be specified inline, i.e. within given tag.

<a style="color:#FF0"></a>


  1. Must be valid according to the DTD file.
  2. Must use utf-8 encoding.
  3. The URL, where the XML is located, must not use redirects and may only contain a maximum of 255 characters.
  4. The XML must contain a definition for all click-throughs (even those which do not change).
  5. The tag “banner” is specified once within the XML.
  6. Graphic creatives must have a correctly set mime-type and size.
  7. Text creatives must have a correctly set mime-type.

Tagging the dynamic parts of the template

Each XML creative will be substituted by a macro with ascending numerical index.

XML for creatives: “creative seq-no="1"” will be replaced in the HTML template with: “img src="__CREATIVE0__"”
XML for click-throughs: “url seq-no="1"” will be replaced in the HTML template with: ”a href="__CLICKTHRU0__"”


  1. The image size in the XML file must correspond with its physical size (e.g. if the following is given: mime-type="image__jpeg" width="110" height="65", the actual picture size must be 110×65 px).
  2. The sequence of the individual creatives has to be as follows: all creatives first (images, texts) followed by all URL addresses.
  3. Numbering of creatives is ascending and starts with the number 1. The list of URL addresses start with the number 1 as well.
  4. Image mime-type in the XML must correspond with the physical image (for a JPG image the following must be given: mime-type="image__jpeg", mime-type for GIF will be ="image__gif" and mime-type for PNG will be ="image__png").
  5. “&” character in URL must be replaced by the entity “& amp;”.
  6. One individual XML document has to be generated for each banner.
  7. The total data size must not exceed the data limit set for each banner size.