Cost Per Impression Calculator

What is cost per impression?

Cost per impression — sometimes shortened to CPI — is what an advertiser pays for a single impression of an ad. An impression is counted each time the ad is served or displayed to someone, so cost per impression is the most granular measure of what your ad exposure costs.

In digital marketing it is the base unit of impression-based pricing — as opposed to click-based pricing — where you pay to be seen whether or not anyone clicks. Because one impression typically costs only a fraction of a cent, the industry more often quotesCPM (the cost of 1,000 impressions). Cost per impression comes into its own when you need precise, per-unit economics rather than a headline rate.

How to calculate cost per impression

To calculate cost per impression, divide the total cost of your campaign by the number of impressions it delivered:

Cost per impression = Cost ÷ Impressions

In two steps: take the total amount spent, then divide it by the total number of impressions. For example, $10,000 spent for 1,000,000 impressions gives a cost per impression of$0.01 — one cent.

Because the formula links three values, you can rearrange it to solve for whichever one you are missing — which is exactly what the calculator above does:

• Find cost per impression — Cost ÷ Impressions ($5,000 ÷ 2,000,000 = $0.0025)
• Find Cost — Cost per impression × Impressions ($0.004 × 500,000 = $2,000)
• Find Impressions — Cost ÷ Cost per impression ($8,000 ÷ $0.005 = 1,600,000)

A worked example

Suppose you spend $10,000 and earn 1,000,000 impressions. Your cost per impression is:

$0.01 = $10,000 ÷ 1,000,000

That is one cent per impression, equivalent to a $10.00 CPM. Working the other way: if your cost per impression is $0.008 and you have a $10,000 budget, that budget buys 1,250,000 impressions ($10,000 ÷ $0.008) — a quick way to check the reach a budget can deliver.

How to use this calculator

1. Choose which value to solve for — cost per impression, cost, or impressions.
2. Enter the two values you already know. Results update instantly as you type.
3. Switch currency if you're planning in something other than dollars.
4. Use Copy shareable link to send the exact scenario to a colleague — the numbers are saved in the URL.

What's a good cost per impression?

There is no universal "good" cost per impression — it depends on platform, audience, format and season, and because the per-impression figure is so small it is almost always judged as aCPM. As a quick orientation, $0.01 per impression equals a $10 CPM, and $0.005 equals a $5 CPM. Broad display sits at the low end, while tightly targeted social or video runs higher.

Rather than chase a single number, compare against real rates for your channel. Ouradvertising benchmarks show typical CPM by industry for Google and Meta, plus CPM by country.

Cost per impression vs CPM

Cost per impression and CPM measure identical things — they only differ by a factor of 1,000:

• CPM = Cost per impression × 1,000
• Cost per impression = CPM ÷ 1,000

CPM stands for cost per mille — Latin for "per thousand" — so a "CPM rate" is simply the cost of 1,000 impressions, and "cost per thousand impressions" means the same thing. In advertising, CPM is the standard way costs are quoted because a single impression costs a fraction of a cent and 1,000-impression pricing keeps the numbers readable. So a $0.01 cost per impression is the same as a $10.00 CPM. If you think in CPM day to day, theCPM calculator is the companion tool; use this page when you specifically need the per-impression figure.

When is cost per impression used?

Cost per impression matters most where per-unit economics are the point:

• Programmatic and real-time bidding — where bids are set and won at the individual-impression level.
• Publisher and ad-network economics — comparing what an impression costs to buy against what it earns.
• Brand-awareness campaigns — measured on reach and exposure rather than clicks.

It sits opposite click-based pricing like cost per click (CPC): impression pricing charges you to be seen, while click pricing charges you only when someone acts. Which model is better depends on whether your goal is awareness or response.