September 5, 2018

The ins and outs of digital ad specs…

This may look like a weird article to make if you’ve ever had agency experience, but if you’re the sole front-end developer of a large company getting ad requests that are, at best, a hand-wavy “just make it go” approach with no documentation, this might save you weeks of head-slapping monotony and explanation.

I’ve been doing this kind of design and development for over a decade, so here is the most comprehensive list of resources and caveats I can think of off the top of my head.

The specs you absolutely need are:

  • ad dimensions
  • file size
  • is it animated (if so, how long is the animation?)
  • imagery to use
  • format (html, GIF, JPG, video)
  • ad copy
  • Alternative copy (if the spec’d copy doesn’t fit in the size or format given)
  • Call to action (where does it link to)

Note: we need at least ALL this information for each ad

to complete the build of the ad set, both from a design perspective and a development perspective. The majority of this content can be obtained from the media company or ad distribution company being used. They are referred to usually as the “Ad Specs”. The companies usually follow the AIB specs. (see below)

IAB ad standard guidelines:

Below are the Standardized modern ad specs for the latest generation of devices. Please be aware of what’s available out there. We can only be as innovative as the jobs we are asked to do.

You can get the Standard Spec Sheet here:

Some General rules of thumb:

  • Animated banners can usually only run for 15 seconds OR loop 3 times.
  • Most ads can only be between 40Kb and 100Kb. So the use of imagery in animated banners should be sparse.
  • Video banners are all over the place for size, and compression codecs, so know what you’re asking for and where it’s ultimately going.

What is the final destination of the ad?

The dimensions in my spreadsheet are the standard dimensions used in the industry for Google, MSN, and Yahoo. However platforms like Twitter, Facebook and Apple’s mobile Ad service use their own specs. So be aware of where they are going.


Other ad specs may fall out of these standards if they are presented exclusively at venues like tradeshows, conferences, digital billboards, or as sponsors within booths. Specs for these use cases will need to be obtained prior to design and development.