Reach vs. impressions
Reach is how many unique people saw your video; impressions are how many total times it was shown. Impressions are always equal to or higher than reach.
Reach counts unique viewers — 200 reach means 200 different people. Impressions count every time the video appeared on a screen, so the same person seeing it twice is 2 impressions but still 1 reach.
Because of that, impressions are always equal to or greater than reach. A big gap between them means people are seeing your video more than once — loops and rewatches — which is usually a good sign on short-form.
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