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Dekodi Team
Return on ad spend is the revenue or conversion value your ads are credited with, divided by what you spent on ads, so $8,000 in attributed sales from $2,000 in ad spend gives you a ROAS of 4.0. That's the short answer. The harder part is knowing whether that 4.0 means you made money.
You know the moment. You spent $2,000 on ads last month, the dashboard shows green arrows, and your bank balance looks quieter than the report promised. Nobody sold you a bad tool on purpose. You just never got one clear line for what counts as winning. That line is what we're building here, step by step.
Table of Contents
What ROAS Means and How to Calculate It
Let's sit with that $2,000 for a minute. The platform dashboard looks healthy, and the bank account tells a calmer story. Both can be true at once, and that's not your fault. It's what happens when a number gets quoted without anyone explaining what it left out.
When you ask what is return on ad spend, the plain answer is this: ROAS is the revenue or conversion value your ads are credited with, divided by what you spent on ads. A conversion is a valuable action a customer takes, like buying, booking, or calling. The Google Business glossary defines ROAS as total conversion value divided by total spend, and the standard formula is ROAS = attributed revenue ÷ advertising cost.
Picture a grocery coupon. ROAS shows the size of the basket the coupon helped fill, not what you kept after paying for the groceries. It tells you how much tracked value came back for each ad dollar. It does not tell you what stayed in your pocket.
How to calculate ROAS in five steps
Run the same five steps every time, and your numbers stay comparable from month to month.
Pull total conversion value: Take the full value your ads were credited with for one date range.
Pull total ad cost: Use the same date range, the same currency, and the same cost scope.
Divide value by cost: That's the whole calculation, value on top, cost on the bottom.
Write it your way: A result of 4.0 can read as 4:1, 4x, or 400%. They all say the same thing.
Check the match: Confirm both numbers cover the same dates and the same definition of a conversion before you compare campaigns.
Two mistakes trip up most owners. The first is dividing by revenue instead of ad spend, which flips the meaning entirely. The second is pairing a full month of sales with one week of ad cost. Mismatched dates make a weak campaign look strong and a strong one look broken.
Worked examples you can check yourself
Google Ads shows this relationship as "conversion value / cost," and Google's guide to conversion value confirms the calculation covers attributed value, not profit after product costs, labor, fulfillment, agency fees, or software. Run these three through the same formula and check the arithmetic yourself.
Example | Attributed value | Ad spend | ROAS | How to read it |
|---|---|---|---|---|
Online store campaign | $8,000 | $2,000 | 4.0 (400%) | $4 of tracked revenue per $1 of ads |
Campaign with assigned conversion value | $5,000 | $1,000 | 5.0 (500%) | $5 of tracked value per $1 of ads |
Six products at $200 each | $1,200 | $200 | 6.0 (600%) | Strong revenue efficiency before $600 in product costs |
Notice what conversion value can include. For a local business, it doesn't have to be an online sale. It can be a booked appointment, a qualified phone call, a sign-up, or a store visit, as long as the value you assign reflects what that action is worth.
One more term, then we're done with definitions. ROI, or return on investment, is the broader measure that subtracts your other costs, like product, staff, fulfillment, and software, before judging the result. ROAS watches the ad spend only. ROI watches the whole picture. Keeping those two apart is the difference between a dashboard that flatters you and one that helps you decide.
How to Read the Number Before Margin
So you ran the formula and got a number. The next question every owner asks is simple: is this good or bad? Before margin enters the picture, read ROAS as a ratio of tracked value to spend, nothing more.
Below 1.0 means your ads were credited with less value than they cost. Spend $1,000, get credited with $700, and you're losing money at the revenue level before a single other cost is counted. There's no margin math that rescues that. The campaign needs fixing or pausing.
Exactly 1.0 means each dollar returned only itself. You spent a dollar and got a dollar of tracked value back. That sounds neutral, but it leaves nothing to cover the product, the staff time, or the software that made the sale possible. In practice, 1.0 is a loss wearing a tidy outfit.
Above 1.0 means tracked value beat the spend. Your 4.0 from earlier means $4 came back for every $1 you put in. That signals real revenue efficiency. It does not prove profit, because the costs behind those sales haven't had their say yet.
A ROAS above 1.0 tells you the ads brought value back. It never, on its own, tells you that you kept any of it.
One honest exception is worth knowing. A campaign that wins customers who keep buying for years may deserve a closer look even when the first-sale ROAS looks modest. That only works if the value you assigned reflects that long-term worth realistically, not hopefully. A guessed value turns the exception into an excuse.
Skip the general rules of thumb you see online about what a good ROAS should be. Your number only means something against your own costs. The break-even line is where this number starts to mean something for your business, and that's where we're headed next.
Why a Strong ROAS Can Still Lose Money
Six products at $200 each bring in $1,200 in sales. If the ads cost $200, ROAS is 6.0. Add the $600 it costs to make or buy those products, and total costs are $800. Profit is $400, so ROI is 50%: $400 divided by $800. ROAS measures revenue against ad spend; ROI measures what remains after the costs in the calculation.
The same campaign can look efficient by one measure and less profitable by another. ROAS is a revenue-efficiency number, not a profit report.
Find your break-even ROAS
Gross margin is the share of each sale left after the product or service cost, before ad spend. If you sell something for $100 and it costs $60 to deliver, your gross margin is 40%.
To find break-even ROAS, divide 1 by your gross margin. At a 40% margin, 1 divided by 0.40 is 2.5. You need $2.50 in revenue per $1 of ad spend to cover that spend. A ROAS below 2.5 loses money before other costs are counted.
Gross margin before ads | Break-even ROAS | Revenue needed per $1,000 of ads | Result at a 3.0 ROAS, before other costs |
|---|---|---|---|
50% | 2.0 | $2,000 | Keeps $500 after ad cost |
40% | 2.5 | $2,500 | Keeps $200 after ad cost |
33% | 3.0 | $3,030 | Roughly breaks even, $10 short after ad cost |
25% | 4.0 | $4,000 | Loses $250 after ad cost |
At a 25% margin, a 3.0 ROAS loses $250 for every $1,000 spent, before other costs. A campaign such as Facebook ads for landscaping businesses needs to be judged against the margin of the work it brings in, not the revenue figure alone.
The costs ROAS never sees
The break-even table does not account for costs outside the margin calculation, such as staffing, software, agency fees, or discounts. If these costs are substantial, your actual break-even point is higher. Set a target above the break-even line so the campaign has room to cover them.
For a service business, use the contribution or profit from acquired customers rather than treating every lead as revenue. Ten inexpensive leads who never answer the phone may be worth less than two customers who book and pay. Your break-even ROAS depends on what remains from the sales your ads generate.
Setting Conversion Values for Local Businesses
Say you run a local service business where almost nobody buys online. People call, they book, they walk in. ROAS still works for you, because conversion value can stand for a booked appointment, a qualified phone call, a sign-up, a store visit, or a qualified lead, as long as the value reflects what the action is worth.
Here's a look at the kind of quiet desk work that makes those values real instead of guessed.
Not every action deserves the same value. A booked appointment with a homeowner who has a real project is worth far more than a low-intent form fill from someone price-shopping three towns away. Give the strong action a strong value, the weak one a small value or none at all. Honest values are what keep the scoreboard honest, the same discipline that matters in PPC for roofers and every other call-driven trade.
This matters more than it used to because of automated bidding, which is the ad platform adjusting your bids for you based on the values you report. Feed it equal values for every form fill and it will chase volume, because that's what you told it a win looks like. Google's Target ROAS guidance uses a 500% target as its example, meaning an average goal of $5 of value per $1 of spend, and it's an average, not a promise for each click or each day. The platform optimizes toward the number you hand it, so counting clicks alone is never enough.
This short walkthrough shows how value based bidding responds to the numbers you feed it.
Setting a value starts with one question: what is a customer won through this channel worth in profit, not in invoice total? Work from average profit, then adjust by action type, with booked work at the top and casual inquiries near the bottom. Try this exercise today: pull your last 20 customers, note how each one found you, and estimate what each was worth in profit. You'll have the raw material for honest conversion values in about half an hour.
Reading ROAS Without Being Fooled by Attribution
A campaign can show different ROAS figures in two honest reports. Attribution and date rules often explain the gap. Attribution is the rule that decides which ad gets credit when a customer sees several ads before buying, whether the first click, the last click, or multiple interactions receive credit.
Date rules can shift a sale between reporting periods. Google's explanation of conversion reporting differences says its primary conversion columns use the date of the ad click, while other analytics systems may use the conversion date. A customer who clicked on Monday and bought on Friday can therefore appear in different weeks depending on which report you open.
Match these four things before you compare
Before judging a campaign's ROAS, make sure both reports use the same rules:
Same date range: Both reports cover identical start and end dates.
Same conversion definition: Both count the same actions as conversions and assign them the same values.
Same attribution model: Both credit the same click or combination of interactions.
Same cost scope: Both include the same campaigns and ad spend.
Practical rule: ROAS figures are comparable only when the accounting rules behind them match. Compare the rules first, then the results.
Disconnected dashboards add work because each can apply different definitions. That makes it harder to tell whether a difference reflects campaign performance or a different way of counting. The same issue can arise when reviewing Facebook page advertising alongside reports from other platforms.
Choose a date rule, a conversion definition, and an attribution model, then record them. Use those same rules to judge every campaign. More options can draw attention; consistent rules make comparisons useful.
Confirm Your Numbers Before Your Next Ad Decision
A campaign can show positive ROAS while creating little or no extra revenue. Some customers would have purchased anyway, but an ad may still receive credit for their orders. Incrementality measures the additional value marketing generates beyond what would have happened without the ads.
A randomized experiment estimates that lift by showing ads to one comparable group and withholding them from another, then comparing outcomes. The Interactive Advertising Bureau's Measurement 360 whitepaper describes incrementality measurement in the context of connecting media activity to business outcomes.
You can also compare similar geographic areas, advertising in one while holding back in another. A before-and-after comparison may offer a rough signal when conditions stay stable. Seasonality, weather, or a competitor closing can affect the result, so treat these comparisons as estimates rather than proof.
Your one step for this week
Before changing your budget, write down your gross margin before ads, average profit per customer, break-even ROAS, and the date range and attribution model used by your dashboard. Put your current ROAS beside the break-even figure. If it is below the line, review the offer, conversion values, and follow-up before increasing spend. If it is above, you have room to test, while still checking whether the ads are generating incremental sales.
Dekodi connects media spend to a funded plan and monitors results against the intended outcome. If you'd like to talk through your numbers and how they relate to your break-even line, visit Dekodi.
