Reach
The number of unique users who saw a post at least once.
What is reach?
Reach counts unique viewers. If 1,000 people saw your post and 200 of them came back to it later, your reach is still 1,000 — each user only gets counted once.
It's not the same as impressions. Impressions count every view including repeats; reach counts heads.
Why reach matters
Reach is the cleanest top-of-funnel metric: how many actual people did this post put in front of? It strips out the inflation that impressions create when the same loyal followers see your post multiple times. For brand awareness goals, reach is the number you optimize.
Where reach gets tricky
- Networks define it differently: Instagram's "reach" includes all users who saw the post in feed, profile, or explore; TikTok's reach is harder to break out from views
- Reach can shrink for an established account: if your follower count grows but your reach drops, the algorithm is showing the post to a smaller fraction of your audience — usually a sign your engagement rate is sliding
- Paid reach vs organic reach: any boosted post mixes both; segment them in reports
How to use it
Pair reach with engagement rate (interactions / reach). High reach with low engagement rate means the post got distributed but didn't land. Low reach with high engagement rate means it landed hard with the few who saw it — likely a candidate for a paid boost.