Google Ads ROI Calculator
Plug in ad spend and revenue. Get ROAS, net profit, ROI %, and the breakeven ROAS your margin demands. No email, no signup.
Pawel Wilk, founder of PerfoAds and Google Ads specialist.
Your numbers
Total Google Ads spend over the period you're measuring.
Revenue attributed to Google Ads (last-click or your model of choice).
Variable cost as a % of revenue. E-com physical: 30-50%. SaaS: 10-25%. Services: 25-50%.
Results
How to read these numbers
ROAS tells you how many dollars of revenue every dollar of ad spend produced. It is operational — it ignores your margin. A 4x ROAS sounds great until you remember that on a 25% margin business it just barely breaks even.
Breakeven ROAS is the floor: the ROAS at which gross profit equals ad spend. Calculate it as 1 / margin. A 30% COGS / 70% margin business breaks even at 1.43x ROAS. A 60% COGS / 40% margin business breaks even at 2.5x ROAS. Any reported ROAS without context of margin is half a number.
Net profit is the dollar number that pays your salary. Gross profit (revenue × margin) minus ad spend. If it's negative, you're losing money on every click — which is fine when paying for new-customer acquisition with positive lifetime value, but catastrophic if those customers don't return.
ROI % is net profit divided by spend, expressed as a percentage. A 100% ROI doubles your money. The mistake most operators make: bragging about high ROI on tiny spend rather than scaling spend to a sustainable ROI floor and capturing far more total profit at lower margin.
Want this math run on your live Google Ads data?
A PerfoAds audit pulls actual ROAS, breakeven, and waste-spend numbers from your account in about 30 minutes, with a secure Google login, a prioritized fix list, and the “PerfoAds Read” of what's actually moving the needle.
Start the audit: $149/mo per accountUp to 10 accounts, $149 each · Cancel anytime