CPM Calculator (Cost Per Mille)
CPM is the price of a thousand impressions — the currency of display, video and social advertising. Solve for any of the three: CPM from spend and impressions, budget needed, or impressions your budget buys.
How to use this calculator
- Choose what to solve for — CPM, budget, or impressions.
- Fill the two known values (the third is ignored).
- Press Calculate. For reach planning, remember impressions ≠ unique people.
Formula used
The M is mille — Latin for thousand. Rearranged: budget = CPM × impressions ÷ 1,000, and impressions = budget ÷ CPM × 1,000. Divide impressions by average frequency (how many times each person sees the ad) to estimate unique reach.
Example calculation
Spend 15,000 for 500,000 impressions: CPM = 30 — i.e. 3 paise/cents per impression.
Planning in reverse: reaching 2 million impressions at that CPM needs 2,000 × 30 = 60,000 of budget.
When CPM is the right lens
CPM prices attention in bulk, which fits objectives where seeing the ad is the point: brand awareness, reach, video views. Auction platforms internally convert everything to effective CPM anyway — a CPC campaign with high CTR is just a cheap CPM buy in disguise, which is why strong creatives effectively pay less.
CPM comparisons need matching context: premium video CPMs run many times banner CPMs, and narrow targeting raises CPM while (ideally) raising value per impression more. The connecting math to performance goals: CPA = CPM ÷ (1000 × CTR × conversion rate).
Why use this calculator?
- Solve any corner of the CPM triangle — price, budget or volume.
- Plan awareness campaigns in impressions and estimated reach.
- Compare placements on the one price every platform ultimately uses.
Frequently asked questions
What is a good CPM?
Hugely context-dependent: broad display can run single digits, social feeds 5–15, premium video and connected TV 20–50+. Judge CPM against the value of the audience and what an impression leads to, not a universal number.
How do impressions differ from reach?
Impressions count views including repeats; reach counts unique people. 500,000 impressions at frequency 2.5 means ~200,000 people. Awareness plans should set frequency caps so budget buys people, not repetition.
How does CPM relate to CPC?
Effective CPC = CPM ÷ (1000 × CTR). At a 30 CPM and 1% CTR, each click effectively costs 3. That identity is how you decide whether buying impressions or clicks is cheaper for your creative.