Cost Per Mille
Definition
The cost per thousand ad impressions. Used in display and brand advertising where you pay for visibility rather than clicks.
What is Cost Per Mille?
Cost Per Mille (CPM) means cost per thousand impressions. "Mille" is Latin for thousand. When you pay CPM, you're paying for your ad to be shown, regardless of whether anyone clicks.
It's the standard pricing model for display advertising and brand awareness campaigns.
How CPM Works
If a platform charges £5 CPM, you pay £5 for every 1,000 times your ad is displayed.
Example:
- CPM: £5
- Impressions: 100,000
- Cost = (100,000 / 1,000) x £5 = £500
CPM vs. Other Pricing Models
| Model | You Pay For | Best For |
|---|---|---|
| CPM | Every 1,000 views | Brand awareness |
| CPC | Every click | Traffic driving |
| CPA | Every conversion | Direct response |
When to Use CPM
CPM works well for:
- Brand awareness campaigns
- Reaching large audiences
- Video advertising
- Display and banner ads
- Remarketing campaigns
CPM makes less sense when you need direct, measurable responses from every pound spent.
What's a Good CPM?
CPM varies hugely by platform and targeting:
- Facebook: £5-15
- Display networks: £1-5
- Premium publishers: £20-50
- Programmatic: £2-10
- YouTube: £5-20
Narrow targeting (specific demographics, interests) costs more than broad reach.
Calculating Effective CPM
If you're running a CPC campaign, calculate eCPM to compare: (Total cost / Impressions) x 1,000
This helps compare performance across different pricing models.