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VAST Video

What is VAST video?

VAST (Video Ad Serving Template) - is a video ad that is served in a video player on publisher’s page.

As it is a skippable ad format, it is more suitable for longer video ads.

The length of a video for this format can vary from very short non-skippable (5 sec.) to long videos of 6 minutes. However, keep in mind that traffic will be limited if you use long video duration, as the most significant part of publishers supports video duration up to 30 sec. Therefore we recommend using videos with a maximum video's duration 30 sec. 

If the video is equal or less than 5 seconds it is served as non-skippable ad and if the duration is from 5 seconds it appears as skippable ad.

The required aspect ratio and dimensions - 720p or below is required, the optional inclusion of 1080p is recommended - either 16:9 or 4:3 aspect ratios are acceptable. (Examples are: 320x480, 480x320, 1024x768, 768x1024)

Requirements summary:

- File Type: mp4

- Maximum Video file size: up to 5MB. 

Here are the examples of VAST video ad on desktop and mobile:



Skip offset

Skip-ability of VAST video can be an important tool for campaign performance. This is why Eskimi has the opportunity to change skip option. By default VAST video can be skipped after 5 seconds. However, it is not sufficient for some advertisers as users will definitely skip the video so it means that brand's message wasn't fully heard. 

Skip option can be edited when VAST video is uploaded. The value should be added under "Skip after seconds" field. 0 - indicates that there shouldn't be any skip option. Keep in mind, that max allowed by protocols is 30s. Default is 5s.


3rd party tracking

To any VAST video campaign 1x1 pixel can be added. VAST video doesn't support JavaScript tags. However, the primary limitation of the 1x1 pixel is that it can only track impressions on 3rd party platforms like Integral Ad Science. 

If the client wants to track more metrics such as viewability, brand safet, IVT on a 3rd party platform VAST video has to be wrapped into a tag. 


  • Max allowed by protocols is 30s. Default is 5s.
  • This functionality is only available on Doubleclick. So the traffic will be limited and will have advertising limitations. 
  • "External VAST URI" won't support this functionality. 


10 sec. tests campaigns got 82% of VCR while regular VAST video delivers around 50% of VCR. 




// BotSonic