Ad Metrics Calculator (ROAS, CPA, CPM, CTR, CPC)

One calculator for every core ad metric

Whether you run Google Ads, Meta, LinkedIn or TikTok campaigns, the same handful of numbers decide whether an ad is working: how much it costs to be seen, to get a click and to win a customer, and how much revenue comes back. Most calculators handle one metric at a time. This one connects them all, so you can enter whatever you know — a budget and a target CPM, or last month’s totals from your ads dashboard — and every other metric that can be worked out appears instantly.

How to use it

1. Enter any values you have in “Campaign totals” (spend, impressions, clicks, conversions, revenue).
2. Add any rates you know, such as an expected CTR or a target CPA.
3. Read the calculated values, shown in green, and the results cards with formulas.
4. Clear a field if you want the calculator to fill it in from the others.

If you enter values that contradict each other — for example spend, clicks and a CPC that don’t match — you’ll see a warning listing the formula that doesn’t add up.

The formulas

• CPM (cost per mille) = Spend ÷ Impressions × 1,000 — the price of reach.
• CTR (click-through rate) = Clicks ÷ Impressions × 100 — how compelling the ad is.
• CPC (cost per click) = Spend ÷ Clicks.
• Conversion rate = Conversions ÷ Clicks × 100 — how well the landing page converts.
• CPA (cost per acquisition) = Spend ÷ Conversions.
• ROAS (return on ad spend) = Revenue ÷ Spend.
• AOV (average order value) = Revenue ÷ Conversions.

These metrics are linked. CPC equals CPM ÷ (10 × CTR), and CPA equals CPC ÷ conversion rate. That’s why a cheap CPM can still produce an expensive CPA if the ad gets few clicks or the page converts poorly — and why it helps to see them together.

Worked example

You spend $1,500 and get 120,000 impressions, 2,400 clicks, 60 sales and $5,400 in revenue. Your CPM is $12.50, CTR is 2%, CPC is $0.63, conversion rate is 2.5%, CPA is $25, AOV is $90 and ROAS is 3.6. That means every dollar spent returned $3.60 in revenue — but whether it’s profitable depends on your margin.

ROAS versus profit

ROAS measures revenue, not profit. To find your break-even ROAS, divide 1 by your profit margin before ad costs. At a 40% margin, break-even ROAS is 2.5; anything above that is profitable. The profit and ROI card uses revenue minus ad spend only, so remember to account for product costs, shipping and fees too.

Track which campaign each result came from by tagging your links with the UTM Campaign URL Builder. For quick percentage changes between periods, use the Percentage Calculator, and bill clients for campaign management with the Invoice Generator.