Identifying optimal viewability for content

One or more computer storage media storing computer-useable instructions that, when executed by a computing device, cause the computing device to perform operations, the operations comprising:

• receiving, at a content server, content requests for content impressions via ad tags launched at user devices in response to the user devices receiving the ad tags from a bidding platform server, each ad tag having been enhanced by the bidding platform server with a content impression identifier or cost data such that each content request includes a content impression identifier or cost data from the bidding platform server;
• receiving, at the content server, in response to pixel tags launched on the user devices during the content impressions, viewability data for each content impression, the viewability data for each content impression comprising a time value for each of a plurality of predefined viewability ranges;
• and
• storing, at the content server, the viewability data for each content impression in association with the content impression identifier or cost data for each content impression.

A computer system comprising:

• a bidding platform server that bids on content impression opportunities and provides ad tags for content impressions won by the bidding platform server, each ad tag being enhanced with a content impression identifier or cost data for each content impression;
• a content server that delivers content with pixel tags for the content impressions in response to content requests based on the ad tags, each content request including the content impression identifier for each content impression or cost data for each content impression, wherein the content server receives, in response to the pixel tags being launched on the user devices during the content impressions, viewability data for each content impression, the viewability data for each content impression comprising a time value for each of a plurality of predefined viewability ranges;
• and
• a cost/viewability engine configured to use the cost data to compute a cost-per-conversion for each of a plurality of groupings of content impressions corresponding to viewability ranges, and that provides a user interface for display that includes information regarding the cost-per-conversion for each grouping.