What is my ROAS, and what is it hiding?
It is the denominator of everything on this page, so it goes first.
What you paid the platforms over one period. For the blended figure to mean anything this has to be ALL of your advertising spend, not one campaign.
Ad spend is the denominator, so nothing can be computed without it. Enter what you paid the platforms over one period, and the revenue those platforms credit to the same period.
- • Needed: ad spend for one period
- • Needed: revenue the platforms attribute to that spend
- • Optional: total store revenue, which adds MER beside the ROAS
Neither figure says whether the campaign made money — that depends on your gross margin. Find the ROAS your margin actually requires.
Nothing you type is sent anywhere. There is no account, no install and no store connection — the arithmetic runs where you are reading it.
ROAS is settled after the click, not before it.
The multiple an ad platform earns is settled the moment the session ends, unless the session leaves an email address first, because the second order from that shopper carries no ad spend at all. Nudgesmart captures it on the storefront, on traffic you have already paid for.
How it's calculated
Return on ad spend is the revenue an advertising platform attributes to your ads divided by what you paid for those ads, so $24,000 of attributed revenue on $8,000 of spend is a ROAS of 3.00x.
No benchmark is used on this page, because there is no published cross-industry ROAS band worth grading against — the bar is set by your gross margin, not by an average. The break-even calculator works out where your own line sits. Nudgesmart publishes no first-party advertising figures, so none are used here.
One division, then a second division that keeps the first one honest. The arithmetic is never the disagreement; the disagreement is always about which revenue counts.
- Ad spend
- What you actually paid the platforms over one period, including any agency or tool fee you want counted. This is the denominator of both figures on the page, and it is the one input where a small definitional choice moves everything downstream.
- Attributed revenue
- Revenue an ad platform credits to its own ads, according to its own attribution window and its own rules about what counts as a touch. It is a claim made by the party being paid. That is not an accusation, it is just what the number is.
- Total store revenue
- Everything the store took over the same period, from your own reporting rather than any platform. Optional here, and the reason the page is worth more than a division: without it you cannot tell a 3.00x that carries the business from a 3.00x that is rounding error on somebody else.
- MER
- Marketing efficiency ratio: total store revenue divided by total ad spend. It has no attribution model, so it cannot be inflated by one and cannot double-count across platforms. It is only meaningful when the spend figure is ALL of your advertising spend — type one campaign into the spend field and MER becomes a flattering number about nothing.
- The gap
- MER minus ROAS, in the same units. A wide gap means most revenue arrives without an ad claiming it, so the ROAS you are optimising governs a small corner of the business. A gap near zero means paid is the business, with very little unattributed revenue to cushion a bad month.
Nudgesmart is available on the Shopify App Store. Browse the template library or see what it costs.
Where ROAS and MER disagree
Illustrative arithmetic, not customer data. Every figure below is produced by the same function the calculator above runs, so the two cannot disagree.
| Scenario | Ad spend | Attributed | Total revenue | ROAS | MER | Attributed share |
|---|---|---|---|---|---|---|
| All paid channels, one month | $8,000 | $24,000 | $46,000 | 3.00x | 5.75x | 52.2% |
| Meta and Google both claiming the same orders | $10,000 | $52,000 | $40,000 | 5.20x | 4.00x | 130%exceeds revenue |
| Brand-heavy store, most revenue arrives without an ad | $3,000 | $6,000 | $60,000 | 2.00x | 20.00x | 10% |
| Scaling month, budget doubled | $20,000 | $44,000 | $62,000 | 2.20x | 3.10x | 71% |
| Retargeting-only budget, flattering ROAS | $1,200 | $9,600 | $38,000 | 8.00x | 31.67x | 25.3% |
| Paid acquisition is the whole business | $25,000 | $50,000 | $52,000 | 2.00x | 2.08x | 96.2% |
Row two is the case worth knowing about: the platforms between them claim 130% of everything the store took, which cannot be true of distinct orders. Row five is the opposite trap — an 8.00x retargeting budget that barely moves the blended figure, because it is spending on people who had already decided.
What this number doesn't tell you
ROAS has no opinion about profit
It divides revenue by spend, and revenue is not money you keep. A campaign at 3.00x is excellent at a 60 percent gross margin and loses money on every order at 20 percent. Nothing on this page can tell those apart, which is why the break-even tool exists.
The period is doing more work than the arithmetic
A 7-day click window and a 28-day view window over the same campaign produce very different ROAS figures from identical sales. Comparing your ROAS to anyone else is usually comparing attribution settings.
A rising ROAS can mean a shrinking business
Cut spend to only the warmest audience and ROAS goes up while total revenue goes down, because the people who would have bought anyway are the cheapest to reach. MER catches that; ROAS applauds it.
MER moves for reasons that have nothing to do with advertising
A good email month, a press mention, a seasonal peak or a single wholesale order all raise MER without a single ad changing. It is a business-level ratio, so read it as a trend over months rather than a verdict on a campaign.
Neither figure knows about new versus returning customers
Revenue from a repeat customer who was going to reorder anyway counts the same as a first order from someone who had never heard of you. Two accounts with identical ROAS can have completely different futures.
Questions
How do I calculate ROAS?
Divide the revenue your ad platform attributes to a campaign by what you spent on that campaign over the same period. $24,000 of attributed revenue on $8,000 of spend is 3.00x. It is a ratio, so it has no currency and no time unit of its own — the period you pick is doing more work than the arithmetic.
What is the difference between ROAS and MER?
ROAS divides platform-attributed revenue by ad spend. MER, or marketing efficiency ratio, divides ALL store revenue by ad spend. ROAS is scored by the party being paid and can be inflated by an attribution window; MER is scored by your bank and cannot. Watched together over time, the gap between them tells you how much of the platform number survives contact with the till.
Why is my attributed revenue higher than my total revenue?
Because each platform attributes independently. A shopper who saw a Meta ad and later clicked a Google ad is counted once by each, so the claimed totals overlap. When the sum exceeds what the store actually took, the individual ROAS figures are not wrong so much as double-counting, and the blended figure is the one to act on.
What is a good ROAS?
There is no cross-industry answer, and any single number quoted as one is wrong for most stores. The bar is set by gross margin: at a 20 percent margin you need 5.00x just to cover the goods, and at 70 percent you need 1.43x. Work out your own line with the break-even ROAS calculator rather than comparing yourself to a listicle.
Does a higher ROAS always mean a better campaign?
No. Narrowing a campaign to its warmest audience raises ROAS and can shrink the business, because the people who would have bought anyway are the cheapest to convert. A retargeting-only budget routinely reports the highest ROAS in the account while moving total revenue barely at all.
Does this tool need my store, an account or an install?
No. It runs in the page, takes figures you already have in front of you, and sends nothing about your store anywhere.
The platforms report the click. The store reports the money.
Nudgesmart works the session the ad has already paid for — a popup targeted on what the shopper is actually doing, reported per campaign.
