CPM Calculator

Find CPM, total ad cost, or impressions from the other two

Last updated: 10/28/2026

CPM means cost per mille, the price of 1,000 ad impressions. This CPM calculator works in three directions: enter cost and impressions to get the CPM, enter a CPM and impressions to get the total cost, or enter a budget and a CPM to see how many impressions it buys.

Calculator Inputs

What do you want to find?*

CPMTotal costImpressions

Total Cost*

What you spent, or plan to spend, on the campaign

Impressions*

Times the ad was shown

Results

Enter values above to see your results

How to use this calculator

Pick what you want to find: CPM, total cost, or impressions.
Enter the two numbers the calculator asks for. Use the same currency for cost and CPM.
Read the result and the breakdown, which also shows the cost of a single impression.

How the calculation works

CPM = (Total cost ÷ Impressions) × 1,000

Total cost = (CPM × Impressions) ÷ 1,000

Impressions = (Budget ÷ CPM) × 1,000

All three are the same formula rearranged. Cost per single impression is the CPM divided by 1,000.

CPM, CPC and cost per impression

CPM prices 1,000 impressions. Cost per impression is the same price for one impression, so it is CPM divided by 1,000. CPC (cost per click) prices clicks instead of views, so it depends on how often people click. If you know your click-through rate as a decimal (2% = 0.02), CPC = CPM ÷ (CTR × 1,000). A $10 CPM at a 2% CTR is 10 ÷ 20 = $0.50 per click.

Publishers often talk about eCPM (effective CPM), which is earnings per 1,000 impressions. The formula is the same, with revenue in place of cost.

Worked example

Find CPM: $500 for 50,000 impressions

Cost per impression:500 ÷ 50,000= $0.01

CPM:0.01 × 1,000= $10.00

Find CPM: $1,500 for 50,000 impressions

Cost per impression:1,500 ÷ 50,000= $0.03

CPM:0.03 × 1,000= $30.00

Find total cost: $8 CPM for 250,000 impressions

Thousands of impressions:250,000 ÷ 1,000= 250

Total cost:250 × $8= $2,000

Find impressions: $1,500 budget at a $12 CPM

Thousands of impressions:1,500 ÷ 12= 125

Impressions:125 × 1,000= 125,000

Tips & Best Practices

•Make sure cost and impressions cover the same date range and the same ads before you compare CPMs.
•A lower CPM is cheaper reach, not better results. Compare it with clicks or conversions from the same campaign.
•CPMs vary by platform, audience, ad format and time of year, so your own past campaigns are the best benchmark.

Frequently Asked Questions

How do you calculate CPM?

Divide the total cost by the number of impressions, then multiply by 1,000. For example, $500 for 50,000 impressions is 500 ÷ 50,000 × 1,000 = $10 CPM.

How do I calculate impressions from CPM?

Divide your budget by the CPM and multiply by 1,000. A $1,500 budget at a $12 CPM buys 1,500 ÷ 12 × 1,000 = 125,000 impressions.

What does CPM stand for?

Cost per mille. Mille is Latin for thousand, so CPM is the cost of 1,000 impressions.

What is the cost per impression if 50,000 impressions cost $1,500?

$1,500 ÷ 50,000 = $0.03 per impression, which is a $30 CPM.

What is a good CPM?

There is no single good number. CPM depends on the platform, the audience, the ad format and the season. Compare against your own earlier campaigns with the same targeting, and judge it together with clicks and conversions.