CPC = spend ÷ clicks. CPM = (spend ÷ impressions) × 1,000. CPA = spend ÷ conversions. Enter any combination below and this calculator returns all three, plus your click-through rate and conversion rate, so you can see exactly where an expensive campaign is leaking money.
Ad cost calculator
Total amount spent on the campaign.
Times your ad was shown. Needed for CPM.
Needed for CPC and CTR.
Sales or leads. Needed for CPA.
—CPC
—CPM
—CPA
—CTR
—Conversion rate
Enter your ad spend plus at least one other figure.
How it works
All three metrics divide the same ad spend by a different denominator, which is why they answer different questions:
CPC (cost per click) = spend ÷ clicks — what you pay for one visitor. CPM (cost per mille) = (spend ÷ impressions) × 1,000 — what you pay to be seen a thousand times, the standard currency of awareness buying. CPA (cost per acquisition) = spend ÷ conversions — what you actually pay for a customer, and the only one tied directly to profit.
Reading them together tells you where the problem is. High CPM means your audience or creative is expensive to reach. Low CTR with cheap CPM means the ad is not compelling. Good CTR but high CPA means the landing page or offer, not the ad, is the bottleneck.
Frequently asked questions
How do I calculate CPC from CPM and CTR?CPC = CPM ÷ (CTR × 1,000). For example a $10 CPM at a 1% CTR gives 10 clicks per thousand impressions, so CPC = $10 ÷ 10 = $1.00. This calculator works it out for you when you enter impressions and clicks.
What is a good CPC or CPM?It varies enormously by platform, industry and audience, so benchmarks are of limited use. What matters is whether your CPA sits below your maximum cost per order. Work that ceiling out with our break-even ROAS calculator.
What is the difference between CPA and CAC?CPA usually measures the cost of a single conversion within one campaign or channel. CAC (customer acquisition cost) is broader, covering all sales and marketing costs divided by new customers won across the whole business.
Why is my CPA so much higher than my CPC?Because only a fraction of clicks convert. CPA = CPC ÷ conversion rate. At a $1 CPC and a 2% conversion rate, each customer costs $50. Improving conversion rate lowers CPA just as effectively as cutting CPC.
Is this ad cost calculator free?Yes. It is free, requires no signup, and runs entirely in your browser so your campaign data never leaves your device.
Paid clicks are rented; your email list is owned. Bluey Email prices per send rather than per contact, so converting expensive ad traffic into subscribers keeps paying you back. Pair this with our ROAS calculator and UTM builder, or see Bluey’s pricing →.