Impressions

Impressions count how many times content was displayed, including repeat views by the same person — unlike reach, which counts people.

Impressions and reach answer different questions. Reach asks how many people; impressions ask how many times. Their ratio is frequency — the average number of times each person saw it — and frequency is often the more actionable of the three.

Because impressions count repeats, they inflate easily. A post that one devoted follower opens nine times produces nine impressions and one person reached. Any metric with impressions as the denominator inherits that inflation, which is why click-through rates on impression-based platforms read lower than intuition suggests.

Definitions also vary by platform: served versus viewable impressions can differ by a third on the same campaign.

In practice

45,000 impressions across 15,000 people is a frequency of 3 — each person saw it three times on average.

Common mistake

Reporting impressions as audience size. It is the most commonly inflated number in creator reporting, and the easiest for a brand to catch.

Impressions

In practice

Common mistake

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