What is CPM (cost per thousand impressions)?
CPM is the cost of showing an ad 1,000 times. It measures how expensive it is to reach people, before anyone clicks.
Formula
CPM = ad spend ÷ impressions × 1,000CPMs rise when competition rises, as in festive and sale seasons, and when an audience is narrow. A high CPM isn't bad on its own if click-through and conversion rates hold up.
Watch CPM together with frequency: a small audience shown the same ad repeatedly gets expensive quickly.
Example
₹12,000 for 80,000 impressions is a CPM of ₹150.