Break even ROAS is the return on ad spend where your ads make exactly zero profit. The formula is 1 divided by your gross margin. At a 50% margin your break even ROAS is 2.0. At a 30% margin it is 3.33. At 25% it is 4.0. Below that number you are losing money on every sale, no matter how good the revenue looks.
This is the single most useful number in a paid media account, and most advertisers have never worked it out. They set a target ROAS because it sounded reasonable, or because someone told them 4x is good.
Below is the math, a full table across margins from 20% to 80%, and how far above break even your actual target should sit.
What is the break even ROAS formula?
Break even ROAS = 1 / gross margin
Gross margin is expressed as a decimal. A 40% margin is 0.40, so break even ROAS is 1 / 0.40 = 2.5.
Here is why that works. Say you sell $100 of product at a 40% margin. You keep $40 in gross profit. To break even, your ad spend has to be exactly $40. ROAS is revenue divided by spend, so $100 / $40 = 2.5. The formula is just that relationship written short.
Check it at another margin. A 25% margin on a $100 sale leaves $25. Ad spend of $25 gives $100 / $25 = 4.0. Which matches 1 / 0.25 = 4.0.
What is my break even ROAS at my margin?
Find your gross margin in the left column. The rest of the row is your break even point.
| Gross margin | Break even ROAS | As a percentage | Ad spend allowed per $100 of revenue |
|---|---|---|---|
| 20% | 5.00 | 500% | $20 |
| 25% | 4.00 | 400% | $25 |
| 30% | 3.33 | 333% | $30 |
| 35% | 2.86 | 286% | $35 |
| 40% | 2.50 | 250% | $40 |
| 45% | 2.22 | 222% | $45 |
| 50% | 2.00 | 200% | $50 |
| 55% | 1.82 | 182% | $55 |
| 60% | 1.67 | 167% | $60 |
| 65% | 1.54 | 154% | $65 |
| 70% | 1.43 | 143% | $70 |
| 75% | 1.33 | 133% | $75 |
| 80% | 1.25 | 125% | $80 |
What this means for you: the last column is the plain English version. At a 30% margin you can spend $30 of every $100 in sales on ads before profit hits zero. Google Ads reports ROAS as a percentage in the interface, so if your break even is 3.33 you are looking for 333% on screen.
Notice how brutal the low margin rows are. A 20% margin business needs a 5x ROAS just to stand still. A 70% margin business only needs 1.43. Margin decides how hard paid media is before you write a single ad.
How do you calculate gross margin properly?
This is where the whole calculation usually goes wrong. Gross margin for advertising purposes means revenue minus every cost that scales with the sale, not just the cost of the product.
Subtract all of these:
- Cost of goods
- Shipping and fulfillment you pay for
- Payment processing fees
- Packaging
- An allowance for returns and refunds
Here is a worked example on a $100 order:
| Line | Amount |
|---|---|
| Order value | $100.00 |
| Cost of goods | $45.00 |
| Shipping and fulfillment | $9.00 |
| Payment processing at 3% | $3.00 |
| True contribution | $43.00 |
| True gross margin | 43% |
| Break even ROAS | 2.33 |
What this means for you: if you had used cost of goods alone, you would have called this a 55% margin business and set break even at 1.82. That gap looks small. It is not.
Run it out. At a 1.82 ROAS with $10,000 of ad spend, you generate $18,200 in revenue. Your true contribution is 43% of that, which is $7,826. Subtract the $10,000 you spent and you are down $2,174. You would have called that month a success.
Why should your target ROAS be higher than break even?
Because break even pays for the product and the ads and nothing else. Rent, salaries, software and your own wage all come out of gross profit too.
The clean way to set a target is to decide what share of gross profit you are willing to hand to the ad platform.
Target ROAS = break even ROAS / share of gross profit spent on ads
Take a business at a 40% margin, so break even is 2.5. Here is what different choices look like:
| Share of gross profit going to ads | Target ROAS | What is left over |
|---|---|---|
| 90% | 2.78 | 10% of gross profit |
| 80% | 3.13 | 20% of gross profit |
| 70% | 3.57 | 30% of gross profit |
| 60% | 4.17 | 40% of gross profit |
| 50% | 5.00 | 50% of gross profit |
Check one row so you can trust the rest. At the 60% row: $100 of revenue gives $40 gross profit. Ads take 60% of that, which is $24. ROAS is $100 / $24 = 4.17. The remaining $16 covers overheads and profit.
What this means for you: pick the row that matches how much of your gross profit the business can actually give away. If your overheads eat 30% of gross profit and you want a 10% margin at the bottom, ads can have about 60%, so your target is roughly 4.17.
Three broad situations, and they call for different targets:
- Funding overheads. Ads have to cover a share of fixed costs. Sit well above break even, usually 1.5 to 2 times it.
- Taking profit now. Same as above but stricter. Every point of ROAS above break even is money you keep, and volume will be lower.
- Buying growth on purpose. You accept a target near or below break even to take market share or build a customer base. This only works if you have the cash to fund it and a real reason to expect the money back later.
When is running at break even actually fine?
When customers come back. If a customer buys three times a year, the first order is not the whole return, it is the entry fee.
Here is the math. Average order value $80 at a 45% contribution margin, so $36 of gross profit per order. Break even ROAS on a single order is 1 / 0.45 = 2.22.
Now say the average customer places 3 orders in 12 months, and the repeat orders cost you nothing in ads.
- Acquiring at break even, 2.22 ROAS. You spend $36 to get the customer. Over the year they deliver 3 x $36 = $108 of gross profit. You are up $72, a 3x return on the acquisition cost.
- Acquiring below break even, 1.5 ROAS. Ad cost per order is $80 / 1.5 = $53.33. You lose $17.33 on the first sale. Across the year you still bank $108 minus $53.33 = $54.67.
What this means for you: the second option makes less per customer but lets you buy far more customers. It is only safe if you have measured the repeat rate rather than hoped for it, and if you have the cash to wait months for the payback. Businesses that guess at repeat rate and run below break even usually run out of money before the theory pays off.
One warning. If your repeat orders happen because of email and retention work, that cost belongs in the model too. It is not free revenue.
How do you use break even ROAS in the ad account?
Break even is a floor, not a bid setting. Never put your break even number into a target ROAS bid strategy, because the algorithm will aim at it and land on both sides of it.
Set your bid target at the profitable number from the table above, then use break even as the line you review against. Anything running below it for a sustained period gets cut or fixed, not tolerated.
A few practical notes:
- Set targets per product group, not per account. If your margins run from 25% to 65%, one account wide target is guaranteed to be wrong for most of your catalog. Our eCommerce PPC strategy guide covers how to split them.
- Feed real margin data in where you can. Sending profit rather than revenue as the conversion value turns ROAS bidding into profit bidding.
- Move targets gradually. Google warns that large changes to a target ROAS restart the learning period. Its Smart Bidding documentation is worth reading before you touch the setting.
- Watch Performance Max especially. It blends channels and will happily hit a target ROAS using traffic that was going to convert anyway. Google describes what it covers in its Performance Max documentation, and we go deeper in our Performance Max guide.
Common questions
How do I calculate break even ROAS?
Divide 1 by your gross margin expressed as a decimal. A 40% margin gives 1 / 0.40 = 2.5, so you break even at a 2.5x ROAS. Use contribution margin after shipping, fees and returns, not just the markup on the product.
What is break even ROAS at a 30% margin?
3.33, or 333% in the Google Ads interface. That means you can spend $30 of every $100 in revenue on advertising before profit reaches zero. To actually make money at a 30% margin you want a target closer to 4.
Is a 2x ROAS good?
Only if your gross margin is above 50%. At exactly 50% a 2x ROAS is break even, so you made nothing. At a 65% margin, 2x is comfortably profitable. At a 30% margin, 2x is a serious loss.
Should I use revenue or profit to calculate ROAS?
ROAS is defined on revenue, which is exactly why it is misleading on its own. Calculate break even from gross profit and use it as your floor. If you can send profit as your conversion value, do that, and read what ROAS is for how the metrics compare.
Can my target ROAS be below break even?
Yes, deliberately, if repeat purchases or subscription renewals make the money back later. It is a cash flow decision, not a marketing one. Do it only with a measured repeat rate and enough cash to fund the gap.
Why is my break even ROAS so high?
Low margins. A 20% margin business breaks even at 5x, which is very hard on paid traffic. The fix is usually pricing, bundling, or raising average order value, not better ad management.
Want your break even worked out on your own numbers?
Our eCommerce advertising team can build the break even math for your catalog and set targets per product group instead of one blanket number. If you run lead generation rather than sales, our Google Ads team does the same thing with close rates and customer value.
No pitch and no commitment. Get in touch and we will run the numbers with you.
