What this estimate measures
The calculator multiplies impressions by your chosen cost per thousand, then adds the values you assign to likes, comments, and shares. An optional sentiment multiplier adjusts the total. Because the same people can both see and engage with a post, this additive model may double-count attention. Use it only as a transparent planning comparison.
Use your own benchmark data
If you have paid campaigns aimed at a similar audience, derive a CPM from their spend and impressions. Assign engagement values only if you can explain where they came from. Different channels and audiences should not share one universal rate. Keep the input assumptions alongside any result you report.
Do not equate this with the value of PR
AMEC's Barcelona Principles warn against using advertising-value equivalents as a measure of public-relations value. Real outcomes may include qualified traffic, inquiries, trust, message understanding, or behavior change; none can be inferred from an impression count alone. Pair an illustrative exposure figure with those outcome measures.