Engagement rate is the share of people who interacted with a post, calculated as total engagements divided by impressions or by followers, expressed as a percentage.
Two common formulas
There is no single standard, so always state which one you use.
| Formula | Calculation | Best for |
|---|---|---|
| By impressions | engagements / impressions x 100 | Comparing posts |
| By followers | engagements / followers x 100 | Comparing accounts |
"Engagements" usually means likes, replies, reposts, and link clicks. Some tools include profile clicks or saves. Networks differ in what their APIs return, so a cross-network number is always approximate.
A worked example
A LinkedIn post has 4,000 impressions and 120 engagements. By impressions, that is 120 / 4,000 x 100 = 3%. The account has 10,000 followers, so by followers it is 1.2%. Same post, two honest numbers.
Why it matters for AI-drafted content
Engagement rate lets you compare posts that reached different audience sizes. If agents draft some posts and people draft others, a fair comparison needs the same formula across both, and enough posts to mean something.
SocialHandoff collects per-post metrics where the network returns them and exposes them to agents through get_insights. Comparisons such as "posts with images got more engagement" are labeled as heuristics, not findings, because small samples mislead. An agent can suggest a change with apply_insight, and the change still goes through review.