Break-Even ROAS and Ad Budget Calculator

Your numbers

Ad platformGoogle reports ROAS as conversion value divided by cost.

Average order valueRevenue per order, before tax.

Gross margin % before adsOrder value minus product, shipping and fees, as a % of order value.

Conversion rate %Orders divided by clicks. Needed for max CPC.

Target ROASRevenue per $1 of ad spend you are aiming for. 3 means $3 back per $1.

Monthly ad revenue goal (optional)Sales you want ads to bring in per month. Gives a budget.

Nothing you type is sent or stored. The math is the same on every platform; only the way each one reports it differs.

Your result

Break-even ROAS

Break-even ACoS

Break-even cost per order

Max CPC at break even

Max CPC at target ROAS

Target ACoS

Profit per order at target

Monthly ad budget

Clicks needed per month

Monthly profit after ads

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How it works

The math behind the calculator

Break-even ROAS = 1 / gross margin. At 40% margin, 1 / 0.40 = 2.5x.
Break-even ACoS = gross margin. ACoS is ad spend / ad sales, the inverse of ROAS.
Break-even cost per order = order value x gross margin
Max CPC at break even = order value x gross margin x conversion rate
Max CPC at target ROAS = order value x conversion rate / target ROAS
Profit per order at target = order value x gross margin - order value / target ROAS
Monthly ad budget = revenue goal / target ROAS, and clicks needed = (revenue goal / order value) / conversion rate

Next step

Know your margin first

Margin

Not sure of your margin?

Work it out per order with our Shopify profit calculator, Amazon FBA calculator or Walmart WFS calculator.

All free tools

Learn

What is a good ROAS?

Break even is the floor, not the goal. Read what a good ROAS looks like for ecommerce and 7 metrics that improve ROAS.

Break-even ROAS guide

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FAQ

ROAS calculator: common questions

What is break-even ROAS?

Break-even ROAS is the return on ad spend where ads pay for themselves and nothing more. It equals 1 divided by your gross margin before ads. With a 40% margin, break-even ROAS is 2.5x: every $1 of ads must bring in $2.50 of sales just to cover itself.

How do I calculate max CPC?

Max CPC at break even is order value times gross margin times conversion rate. With a $50 order, 40% margin and 2% conversion rate, that is $0.40 per click. To leave room for profit, use max CPC at your target ROAS instead: order value times conversion rate divided by target ROAS.

What is the difference between ROAS and ACoS?

ROAS is ad sales divided by ad spend. ACoS, the metric Amazon Ads shows, is ad spend divided by ad sales. They are inverses: 25% ACoS is 4x ROAS. Your break-even ACoS equals your gross margin.

Is break-even ROAS the same on Google, Meta and Amazon?

The math is the same, because it only depends on your margin. What differs is how each platform counts conversions and over what attribution window, so a 3x on Meta and a 3x on Google may not describe the same sales. Compare each platform against your own order data.

How do I set a monthly ad budget?

Divide the monthly revenue you want from ads by your target ROAS. For $10,000 in ad-driven sales at a 3x target, plan about $3,333 of spend. Check the clicks needed result against how much search or audience volume actually exists.

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