Overview
CPM, or cost per mille, is the cost to reach one thousand impressions. 'Mille' is Latin for thousand. It is a standard way to compare the price of reach across different ads and placements.
On TikTok Shop, CPM helps you understand how expensive it is to put your product in front of audiences through paid placements.
How it works
Divide total ad spend by impressions, then multiply by 1,000. $500 spent for 200,000 impressions is a $2.50 CPM.
Why it matters
CPM is a useful efficiency check on the reach side, but cheap impressions mean nothing if they do not convert. Read CPM alongside CTR and conversion rate to judge whether low-cost reach is actually productive.
How brands use it
Brands track CPM to spot when audiences are getting expensive or when creative fatigue is driving costs up, then refresh content or retarget to bring it back down.
