How to Calculate CPM

If you know your spend and impressions, you can calculate CPM in a few seconds.

For the fastest answer, enter those two numbers in the free CPM Calculator, then use the steps below to understand the formula behind the result.

The CPM formula

CPM = (Cost / Impressions) × 1,000

You only need two numbers:

• Cost = total money spent
• Impressions = total times the ad was shown

Step-by-step example

Say a campaign spent $480 and delivered 120,000 impressions.

Step 1: Divide cost by impressions

480 / 120,000 = 0.004

Step 2: Multiply by 1,000

0.004 × 1,000 = 4

Your CPM is $4.00.

Reverse CPM calculations

Sometimes you need the formula in reverse.

Find impressions from budget and CPM

Impressions = (Budget / CPM) × 1,000

Example:

$1,200 budget / $6 CPM × 1,000 = 200,000 impressions

Find budget from impressions and CPM

Budget = (Impressions / 1,000) × CPM

Example:

300,000 impressions / 1,000 × $8 = $2,400

Quick CPM check table

What changes your CPM

• audience competition
• bidding strategy
• placement quality
• geography
• seasonality
• creative relevance

Calculate CPM instantly

Use the free CPM Calculator to get the result instantly, check reverse CPM scenarios, and avoid hand-calculation mistakes.