CPM (Cost Per Mille)

CPM stands for Cost Per Mille. Mille is the Latin word for thousand. It is the price you pay to have your ad shown to 1,000 people. CPM is the foundational cost metric in digital advertising. Every other performance metric builds on top of it.

CPM = (Total ad spend / Total impressions) x 1,000

If you spent $50 and your ad was shown 10,000 times, your CPM is $5.

The Simple Version

CPM measures how expensive it is to get eyeballs. A CPM of $8 means it costs $8 to show your ad to 1,000 people. A CPM of $20 means you are paying $20 for the same 1,000 impressions. Lower CPM gives you more reach for the same budget, which means more opportunities for clicks and conversions.

What Drives CPM

CPM fluctuates based on:

• Competition: More advertisers targeting the same audience pushes CPM up
• Seasonality: Q4 and holiday periods drive CPMs sharply higher as more brands advertise
• Audience targeting: Niche, highly specific audiences tend to have higher CPMs than broad targeting
• Ad quality: TikTok’s algorithm rewards engaging content with better (cheaper) placement. A video with strong engagement signals can earn lower CPM than a poor-performing creative

CPM on TikTok

TikTok CPMs are generally lower than comparable Facebook or Instagram CPMs, particularly for broad audience targeting. This is part of why TikTok Shop VSA campaigns can be cost-effective entry points for new e-commerce sellers. Lower CPMs mean more impressions per dollar while the algorithm is still learning which audiences convert best.

A benchmark under $10 CPM is generally healthy for TikTok. Campaigns regularly achieve $5–8 CPM in early testing with broad targeting. ROAS tells you whether those impressions are translating into profitable sales.

How It’s Used on This Site

CPM is covered in the TikTok Shop blog series as part of the ad performance metrics every new seller needs to understand. The glossary connects it to the full diagnostic chain: CPM measures reach cost, CTR measures engagement, CVR measures purchases, and ROAS measures profitability.