Paid media basics
Cost per thousand impressions (CPM)
What it costs to show an ad a thousand times.
What it is
CPM is the price of attention on a platform. It rises with competition for the audience and falls when the platform judges the ad more engaging.
Why it matters
For lead generation and e-commerceIt is the starting price of every result: a lower CPM with the same click and conversion rates means cheaper customers.
How it is measured
Formula
CPM = spend / impressions x 1,000Divide spend by impressions and multiply by a thousand.
A common mistake
Chasing low CPMs. Cheap impressions often come from audiences or placements that rarely buy.
All terms