CPM Calculator
By Talcart · Last updated July 10, 2026
Cost Per Mille (CPM) Guide
Understanding CPM
Basic Formula
CPM = (Total Ad Cost / Number of Impressions) × 1000
Example: ($1,000 / 100,000 impressions) × 1000 = $10 per thousand impressions
Usage
Common in display and brand awareness campaigns
Higher CPM often indicates premium ad placement
CPM Calculator
This CPM calculator converts ad spend and impressions into cost per thousand impressions, the standard price unit of display, social, video and out-of-home media. Spend $1,000 to serve 200,000 impressions and your CPM is $5.00. It also solves the planning inversions: what a budget buys at a quoted CPM, and what a target impression volume will cost.
Key facts
- CPM = (spend ÷ impressions) × 1,000: $1,000 for 200,000 impressions is a $5.00 CPM.
- At a $10 CPM, $1,000 buys 100,000 impressions; one million impressions cost $10,000.
- CPM-to-CPC bridge: at a $10 CPM and 2% CTR, each click effectively costs $0.50 (20 clicks per 1,000 impressions).
What is the CPM Calculator?
CPM (cost per mille, from the Latin for thousand) is the price an advertiser pays for one thousand ad impressions. It is the dominant pricing model for awareness media — display banners, online video, connected TV, podcasts and billboards — where the advertiser buys exposure rather than clicks. Because CPM normalises cost to a fixed unit of delivery, it lets buyers compare wildly different inventory on one scale: a $4 CPM banner network against a $30 CPM premium video placement, for instance.
How does the CPM Calculator work?
The core formula is CPM = (Spend ÷ Impressions) × 1,000. It rearranges into the two questions media planners actually ask: Impressions = (Budget ÷ CPM) × 1,000, so $1,000 at a $10 CPM buys 100,000 impressions; and Cost = (Impressions ÷ 1,000) × CPM, so one million impressions at a $5 CPM costs $5,000. Publishers use the same arithmetic in reverse as eCPM — revenue per thousand impressions served — to compare income across ad formats.
What is the CPM Calculator formula?
- Spend – total ad spend
- Impressions – total impressions delivered
What a budget buys at common CPM rates
| CPM | Impressions per $1,000 | Cost of 1,000,000 impressions |
|---|---|---|
| $2.00 | 500,000 | $2,000 |
| $5.00 | 200,000 | $5,000 |
| $8.00 | 125,000 | $8,000 |
| $10.00 | 100,000 | $10,000 |
| $15.00 | 66,667 | $15,000 |
| $25.00 | 40,000 | $25,000 |
| $50.00 | 20,000 | $50,000 |
How do you use the CPM Calculator?
- Enter total spend.
- Enter total impressions.
- Read CPM.
Worked example
| Scenario | $1,000 for 200,000 impressions |
| Calculation | 1000 / 200000 × 1000 |
| Result | CPM $5.00. |
Common use cases
Tips & best practices
CPM is for impressions; pair with view-through-rate or attention metrics for true value.
Frequently asked questions
Divide total spend by total impressions and multiply by 1,000: CPM = (Spend ÷ Impressions) × 1,000. A campaign that spent $1,000 to deliver 200,000 impressions has a CPM of $5.00. The multiplication by 1,000 exists purely for readability — per-impression prices would be tiny fractions of a cent.
CPM stands for cost per mille, where mille is Latin for one thousand — so it is the cost of one thousand ad impressions. The unit dates from print advertising, where rates were quoted per thousand copies circulated, and carried over unchanged to digital display, video and audio. It is sometimes written as CPT (cost per thousand) in older media contexts.
Exactly 100,000 impressions: divide the budget by the CPM and multiply by 1,000, so ($1,000 ÷ $10) × 1,000 = 100,000. The same budget stretches to 500,000 impressions at a $2 CPM and shrinks to 20,000 at a $50 CPM. Reach planning is just this division applied to your target audience size and desired frequency.
Buy on CPM when the goal is exposure — brand awareness, launches, retargeting reminders — and on CPC when you only value visits. If your ads earn a high click-through rate, CPM buying is often cheaper per click: at a $10 CPM, a 2% CTR yields 20 clicks per 1,000 impressions, an effective $0.50 per click. With a weak CTR the same math flips in favour of paying per click.
eCPM (effective CPM) is revenue or cost normalised to one thousand impressions regardless of how the deal was actually priced. Publishers compute it as (Earnings ÷ Impressions) × 1,000 to compare income from CPC, CPM and CPA demand on one scale. An ad unit earning $150 from 50,000 impressions runs a $3.00 eCPM — whichever pricing produced the money.
No — CPM prices delivery, not quality, so the cheapest impressions are often the least visible or worst targeted. A $2 CPM placement with 20% viewability effectively costs $10 per thousand viewable impressions, more than a $8 CPM placement at 90% viewability ($8.89). Judge CPM alongside viewability, audience fit and outcomes, not as a standalone score.