You spent $1,000 on ads and brought in $900 in revenue. Did the campaign work? Plenty of people would say it nearly broke even. In reality, you lost money twice: once on the ad spend, and again on the product costs, shipping, and fees behind those $900 in sales.
A ROAS calculator gives you the ratio in seconds, but the number only helps if you know what it’s telling you. A 0.9 looks harmless until you compare it with your margins. A 4.0 looks great until you realize your costs eat most of it.
This guide covers the basic formula, how to run it in a spreadsheet or an online tool, and how to convert ROAS to ACoS and back. You’ll also learn how to find your break-even ROAS and see how it plays out in real examples. One caution before we start: ROAS measures revenue against ad spend only. It doesn’t show your total business profit, so treat it as one input, not the final verdict.
How to Calculate ROAS (Formula, Excel and Online Calculators)
The formula is simple: ROAS = revenue from ads ÷ ad spend. If you spend $2,000 and your ads bring in $6,000 in tracked sales, your ROAS is 3.0x.
You’ll see the result written two ways. As a ratio, it’s 3.0x (or 3:1). As a percentage, it’s 300%. Same number, different format. Multiply the ratio by 100 to get the percentage.
Build a ROAS calculator in Excel
You don’t need software for this. Open a sheet and use three cells:
- A2: ad revenue
- B2: ad spend
- C2: =A2/B2
Format C2 as a number for the ratio, or as a percentage for 300%. If you’d rather skip the setup, a free ROI and ROAS calculator does the same math.
ROAS vs. ROI
People mix these up constantly. ROAS only looks at ad spend. ROI looks at profit after all costs. Take that $6,000 in revenue with $2,000 in ads and $3,000 in product costs. ROAS is still 3.0x, but ROI is $1,000 profit on $5,000 of total cost, or 20%.
What Does a ROAS of 1.5 or 2.5 Mean? And What ROAS Is 25% ACoS?
A ROAS of 1.5 means every $1 you spend on ads brings back $1.50 in revenue. That sounds positive, but revenue isn’t profit. Once you pay for the product, shipping and fees, most businesses lose money at 1.5.
A ROAS of 2.5 brings back $2.50 per $1. Whether that pays off depends on your margins. At a 50% margin, you keep $1.25 in gross profit and clear $0.25 after the ad cost. At 30%, you keep $0.75 and lose $0.25. Same ROAS, opposite outcomes. Looking at what it costs to collect your revenue makes that gap easier to see.
Converting ACoS to ROAS
ACoS is ad spend divided by ad revenue, so it is simply the inverse of ROAS: ROAS = 1 ÷ ACoS.
For a 25% ACoS, divide 1 by 0.25 and you get 4.0. Quick check: spend $25, earn $100 in sales. That’s 25% ACoS and a 4.0 ROAS. It works the same way as any return on investment ratio.
Break-Even ROAS: The Number Your Costs Actually Decide
Break-even ROAS is the point where ad revenue exactly covers your costs. The formula is simple: 1 ÷ your profit margin. Margin here means what’s left of each sale before ad spend.
Say you keep 40% after product costs. Divide 1 by 0.40 and you get 2.5. Every $1 you spend on ads has to bring back $2.50 in revenue just to leave you at zero.
The dropshipping version
Dropshippers often start with the wrong margin. Selling price minus supplier cost isn’t enough. Also subtract:
- Shipping costs
- Payment fees, including PayPal charges
- Refunds and chargebacks
A product that looks like a 40% margin may be closer to 30% once those are out. That moves your break-even from 2.5 to about 3.3.
Service businesses face the same issue. If you advertise installations, your margin depends on labor and materials, so it helps to understand gutter installation costs before you set a target.
Anything above break-even is profit. Anything below it loses you money, even when the dashboard looks busy.
What Is a Good ROAS, and Why Your Campaign Numbers Vary
There is no universal benchmark. A 3x ROAS can be great for a store with 25% margins and a loss for one with 30% margins and heavy shipping costs. Start from your break-even point, then decide how much profit you want above it.
Platforms behave differently, too. Search captures people already looking to buy, so ROAS often runs higher. Facebook, TikTok and Snapchat interrupt people, so they usually need stronger creative and more patience. Judge each channel by its role, not by one shared target. Long-cycle offers, like the tuition-based programs in our Keiser University guide, also take longer to show returns.
Fix these before raising spend
- Offer: test a clearer deal or a bundle.
- Landing page: match the ad message and speed up load time.
- Audience: cut segments that never convert.
- Average order value: add upsells or a free-shipping threshold.
- Seasonality: compare against the same period last year.
Your Next Step: Know Your Margin, Then Measure
A ROAS number only means something next to your break-even ROAS. Calculate one, then compare it with the other. If you’re above the line, you’re making money. If you’re below it, you’re paying to make sales.
Start by setting your margin, since everything else depends on it. Then test small: put a modest budget behind one campaign before you scale. Log ROAS once a week in a simple spreadsheet with spend, revenue and the ratio. After a month or two, you’ll see which campaigns earn their budget.
Frequently Asked Questions
How do you calculate ROAS?
ROAS is calculated by dividing your total revenue by your total ad spend. For example, if you spent $1,000 on ads and generated $5,000 in revenue, your ROAS would be 5:1 or simply 5. This metric shows how much revenue you earn for every dollar spent on advertising.
What does 2.5 ROAS mean?
A ROAS of 2.5 means you're earning $2.50 in revenue for every $1 spent on advertising. This is generally considered a healthy return, indicating your campaigns are profitable. Most businesses aim for at least 2:1 ROAS to cover costs and generate profit.
What does a ROAS of 1.5 mean?
A ROAS of 1.5 means you're generating $1.50 in revenue for every $1 spent on ads. While this indicates profitability, it's considered below average for most industries. You're only making 50 cents in net revenue after covering your advertising costs.
What ROAS is 25% ACoS?
A 25% ACoS (Advertising Cost of Sale) equals a ROAS of 4:1 or 4.0. This is calculated by dividing 100 by the ACoS percentage. A 25% ACoS is excellent, meaning you're spending just 25 cents to generate every dollar in sales.
