VAST best practices

In AdButler's VAST video ad format, you have the option to add additional linear media files on your VAST ad item ad. Using alternate file formats and resolutions allows your VAST-compatible video player to choose the best file format and resolution for the viewer.

Recommended Name Format

ad item name format, and eliminate "&", ";" or "%" characters in your file names. We recommend that you use camel case, include the size, and seperate important info with an "_". For example: "FallFishingPromo_640x480.mp4".

Other platforms may have additional restrictions on character usage. They might restrict "&", ";", ".", "%", "+" and spaces. For maximum compatibility across all platforms, do not include these characters in your file name formats.

Best File Formats and Resolutions

For maximum compatibility across browsers, generally we recommend that you include the two main HTML5 video file types: MP4(H.264), and WEBM. For file sizes, you'll want to ensure that you provide some type of high, mid and low quality options for the player to choose from. For resolution sizes, it is a good idea to cover the 3 common aspect ratios: 4:3, 16:9, and 5:2.

Some great tools for converting the variable file formats needed are Handbrake (MP4) and Firefogg (WEBM).

Below is a graph of the recommended formats and file types for VAST ads:

Resolution sizes File Types File size Video length Frame rate
Include enough options to allow video ads to render in any sized player.
Examples: (4:3) (16:9) (5:2)
H.264 (MP4) and WebM, both formats are required.

MP3 or AAC preferred.
10 MB (maximum), less than 3 MB (recommended) 60 seconds (maximum) 30 FPS (maximum)

In order to meet the minimum requirement for VAST ad serving you must include (1) mp4 file and (1) webm file. Below is a screenshot showing where you can upload your additional media files when creating a VAST ad item:

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