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Defining an impression is tricky — and often confused with social media reach.
http://garrygolden.com/march4/ The way we define an impression can vary by social platform, type of content, how much of your content is visible on screen, and sometimes by how long the content is visible to someone.
Yeah, it’s sort of complicated.
There are impressions that require someone to see your video story for a minimum of 2 seconds, 15 seconds or even a specific amount of time (e.g. 25% of your video story must be seen on Snapchat for certain impressions).
There are also impressions that require your content to be visible for at least one second — and at least 50% visible on screen (e.g. YouTube thumbnails visible appearing briefly on your mobile device while you scroll).
There are too many definitions out there and I have to look up the definitions regularly.
This is why we should try to always provide exact definitions in our social media reporting and not assume that people know what an impression means.
In general, reach refers to the total number of people who see your content. Impressions refer the number of times your content was displayed, but that depends on each networks definition.
