Return on ad spend and profit are different things, and most owners who search this question treat them as the same number. ROAS tells you how much revenue your ads were credited with for each dollar spent on them. Profit tells you what is left after every cost, including the product, the labor, the fees and the ads themselves. You came here for the ROAS formula, and it is short. The harder part is knowing what the result does and doesn't prove, so this page covers both.
The formula, in plain words
ROAS equals the revenue your ads are credited with, divided by what you spent on those ads over the same period. It is a ratio, usually written with an x after it. Suppose the ratio comes out above the amount you spent: that means the ads brought in more revenue than they cost. It does not mean you made money. Revenue is the money customers paid, not the money you kept.
Two habits keep the calculation honest. Use the same date range for the revenue and the spend. And count only spend that belongs to the campaigns whose revenue you are counting, not your whole marketing budget.
| Metric | What you divide | Question it answers |
|---|---|---|
| ROAS | Ad-attributed revenue by ad spend | How much revenue did each ad dollar bring in? |
| Break-even ROAS | Revenue by gross profit on that revenue | How low can ROAS fall before the ads lose money? |
| Cost per acquisition | Ad spend by number of customers or orders won | What did each new sale cost to win? |
| Return on investment | Profit after all costs by total cost | Did the whole effort make money? |
Why a healthy-looking ratio can still lose money
A ratio that sounds impressive can sit on top of thin margins. If most of each sale goes to materials, shipping, payment fees, discounts and refunds, very little is left to pay for the ad that produced it. Two businesses can post the same ROAS, and one can be growing while the other quietly loses cash on every order.
The fix is to work out your break-even ROAS before you set any target. Take your revenue and divide it by the gross profit on that revenue, meaning what remains after the direct cost of delivering the product or service. That result is the floor. Below it, every ad dollar loses money on the first sale. Above it, you are covering costs and contributing to overhead and profit.
Where the revenue figure really comes from
The revenue half of the formula is where most of the confusion lives. Each ad platform reports the sales it takes credit for, using its own rules about how long after a click or a view a sale still counts. Two platforms can each claim the same order, so the totals in your dashboards may add up to more than your bank account shows. Phone calls, in-store visits and quotes closed weeks later often go uncounted, which pushes ROAS the other way.
Treat the platform figure as a working estimate. Compare it against your own sales records for the same period. If the gap is large, the cause is usually tracking setup, not the ads.
Who asks this, and what advertisers pay nearby
This is a small, specific question. Across 2 distinct phrasings, roughly 180 searches a month look for the calculation itself. Advertisers targeting nearby marketing-help searches bid as much as $55.20 for a top-of-page click. That figure is a ceiling set by agencies and software vendors competing for each other's customers. It says nothing about what your own ads cost.
A routine you can run this week
Pull the revenue and spend for one campaign over a period long enough to include your normal sales cycle. Divide to get ROAS. Then work out your gross profit on those same sales and calculate break-even ROAS. Put the two side by side. If ROAS clears break-even with room to spare, note whether the customers came back, since repeat business improves the picture. If it lands near break-even, look at margin and conversion before you touch the budget. If it falls below, pause and check the tracking before you blame the ad.
Signs a second pair of eyes is worth it
You can do the arithmetic yourself, and for a small account you probably should. Outside help becomes reasonable when the inputs stop being trustworthy: platform revenue and your own records disagree, calls and form fills aren't being counted, or you can't tell which campaigns deserve more money. A tracking review can settle those questions without you changing anything about how you advertise. Whether you do that in-house or with a specialist is a call about your time, not something the ratio forces on you.