Free tool · CPM

CPM calculator.

Cost per thousand impressions from any campaign, or how far a budget stretches at a given CPM.

Runs in your browser. Nothing is uploaded or stored.
  1. 1Type your own numbers on the left. Everything updates as you type.
  2. 2Read the results on the right. The highlighted figure is the one that matters most.
  3. 3Copy the link to share these exact numbers, or switch currency at the top.

Work out CPM

Or: what a budget buys

CPM–

Cost per 1,000 impressions

Cost per single impression–
Your budget buys–

Exchange rates: fallback table dated 2026-10-01. Live rates load from Frankfurter when available.

The CPM formula

CPM = (cost ÷ impressions) × 1,000
Impressions = (budget ÷ CPM) × 1,000

Worked example

A Manchester takeaway spends £300 on a Meta awareness campaign that serves 60,000 impressions. CPM is (300 ÷ 60,000) × 1,000 = £5. If the next month's budget is £1,000 at the same CPM, it buys 200,000 impressions. Whether that is good depends on frequency: 200,000 impressions to 20,000 people is ten views each, which is plenty for a local brand and probably wasteful beyond that.

When CPM matters

CPM is the right lens for awareness and reach campaigns, where the job is to be seen. For lead and sales campaigns, judge on cost per result instead. We use CPM mainly to spot creative fatigue (rising CPM with falling CTR) and to compare placements before scaling.

FAQ

CPM calculator: questions answered.

What is CPM?

Cost per mille, or cost per thousand impressions. It is what you pay for your ad to be shown 1,000 times, whether or not anyone clicks.

What is the CPM formula?

CPM = (total cost ÷ impressions) × 1,000. Spending £300 for 60,000 impressions gives a CPM of £5.

Is a low CPM good?

Only if the impressions reach the right people. A £2 CPM on an audience that never buys is worse than a £12 CPM that converts. Use CPM to compare placements and creatives within the same audience, not across different audiences.

Which platforms charge by CPM?

Meta, TikTok, Snapchat and LinkedIn bill mostly by impressions. Google Search bills by click, but Display, YouTube and Performance Max placements are effectively bought on CPM and vCPM.

Why does my CPM go up when I scale?

The platform has to reach less responsive people once the easy audience is saturated, and your ads start competing with themselves. Fresh creative and broader audiences usually bring it back down.

What is vCPM?

Viewable CPM: cost per thousand impressions that were actually viewable on screen. It is the better measure for awareness campaigns.

How do I convert CPM to cost per click?

CPC = CPM ÷ (CTR × 10). With a £6 CPM and a 1.5% CTR, each click costs £0.40. The CPC calculator does this for you.

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