# CPM calculator

https://salesbond.app/tools/cpm-calculator/
Updated: 2026-11-05

# CPM Calculator (CPC, CPA and ROAS)

CPM is the cost per 1,000 impressions: ad spend ÷ impressions × 1,000. Spending 500 for 100,000 impressions is a CPM of 5.00. With 2,000 clicks the CPC is 0.25, with 40 sales the CPA is 12.50, and 2,000 of revenue means a ROAS of 4: 1, or 400%.

Enter your ad spend and whatever you know, from impressions and clicks to conversions and revenue, to get CPM, CPC, CTR, CPA, conversion rate and ROAS at once in any currency. Or plan a campaign: the cost of impressions at a given CPM, or how many impressions a budget buys.

## CPM, CPC, CPA and ROAS formulas

CPM = spend ÷ impressions × 1,000. CPC = spend ÷ clicks. CTR (%) = clicks ÷ impressions × 100. CPA = spend ÷ conversions. Conversion rate (%) = conversions ÷ clicks × 100. ROAS = revenue ÷ spend (× 100 for a percentage). Cost of a campaign = CPM × impressions ÷ 1,000.

## Worked example

| Case | Result |
| --- | --- |
| Spend 500.00, 100,000 impressions: CPM | 5.00 |
| 2,000 clicks: CPC, CTR | 0.25, 2.00% |
| 40 conversions: CPA, conversion rate | 12.50, 2.00% |
| Revenue 2,000.00: ROAS | 4: 1 (400.00%) |
| Budget 1,000.00 at a CPM of 12.00: impressions | 83,333 |

## Which metric to watch

CPM tells you what attention costs and suits awareness campaigns. CPC and CTR show whether the ad earns the click. CPA and cost per lead show what a customer or a lead costs, and ROAS whether the spend comes back as revenue. A cheap CPM with a poor CPA is not a bargain: judge a campaign by the metric closest to the money.

## Break-even ROAS

Revenue is not profit. To find the ROAS at which ads pay for themselves, divide 1 by your gross margin: with a 40% margin, break-even ROAS is 1 ÷ 0.40 = 2.5: 1. Check your margin with the [gross profit calculator](https://salesbond.app/tools/gross-profit-calculator/) and tag each campaign with the [UTM builder](https://salesbond.app/tools/utm-builder/) so revenue is attributed to the right ad.

## Frequently asked questions

### How do you calculate CPM?

Divide the ad cost by the number of impressions and multiply by 1,000. A campaign that spends 500 on 100,000 impressions has a CPM of 500 ÷ 100,000 × 1,000 = 5.00. CPM stands for cost per mille, mille being Latin for a thousand.

### How do I calculate ROAS?

Divide the revenue the ads brought in by what you spent on them. 2,000 of revenue from 500 of spend is a ROAS of 4: 1, or 400%. A ROAS below 1: 1 means the ads cost more than they brought back, before any product costs.

### What is the difference between CPC and CPA?

CPC is the cost per click: spend ÷ clicks. CPA is the cost per acquisition, a sale, lead or sign-up: spend ÷ conversions. With 500 of spend, 2,000 clicks and 40 conversions, CPC is 0.25 and CPA is 12.50.

### How many impressions will my budget buy?

Divide the budget by the CPM and multiply by 1,000. A budget of 1,000 at a CPM of 12 buys about 83,333 impressions. The real CPM changes with the audience, the placement and the season, so treat the number as a plan, not a promise.

### What is a good ROAS?

It depends on your margin. If your gross margin is 40%, you need a ROAS of at least 2.5: 1 (1 ÷ 0.40) just to cover the product cost and the ads; anything above that is profit. Work out your margin first with the gross profit calculator.

### How do I calculate cost per lead?

Treat leads as conversions: cost per lead = ad spend ÷ leads. 500 of spend that brings 40 leads costs 12.50 a lead. Then compare it with how many leads become customers and what a customer is worth.

Related tools: [conversion rate calculator](https://salesbond.app/tools/conversion-rate-calculator/), [gross profit calculator](https://salesbond.app/tools/gross-profit-calculator/), [UTM builder](https://salesbond.app/tools/utm-builder/). More on sales and running a sales team on the [SalesBond blog](https://salesbond.app/blog/) and the [home page](https://salesbond.app/).

## Official sources

- [Google Ads Help: cost-per-thousand impressions (CPM)](https://support.google.com/google-ads/answer/6310) — cost per 1,000 impressions.
- [Google Ads Help: cost-per-click (CPC)](https://support.google.com/google-ads/answer/116495) — average CPC = cost ÷ clicks.
- [Google Ads Help: clickthrough rate (CTR)](https://support.google.com/google-ads/answer/2615875) — clicks ÷ impressions.
- [Google Ads Help: about Target ROAS bidding](https://support.google.com/google-ads/answer/6268637) — conversion value ÷ cost.

**Updated on Nov 5, 2026.** This calculator is for information only and is not tax, legal or payroll advice. Results come from the formulas above; ad platforms may count impressions, clicks and conversions differently.