ROAS formula: how to calculate return on ad spend, and what a good ROAS is.

Your Google Ads dashboard looks healthy. A ROAS of 400%: four euros in revenue for every euro of ad spend. Yet at the end of the month, there is surprisingly little left. That is not an error in the platform. ROAS measures revenue, not profit, and the number only means something once you put it next to your margin.

The fix is to read ROAS against your own margin, not against a rule of thumb. This guide covers the ROAS formula, a worked example and an honest answer to what a good ROAS is. You will calculate your break-even ROAS and your target ROAS, see where ROAS lives in Google Ads, GA4 and Meta Ads Manager, and learn when profit on ad spend (POAS) is the better number to steer on. Definitions and settings come from Google Ads Help, Meta Business Help and Amazon Ads; the worked examples are ours, with a calculator along the way and a free worksheet at the end. At Viralistic we never report ROAS on its own: every campaign answers to what it leaves behind after the margin. ROAS is one of the best-known marketing KPIs, and one of the easiest to misread.

What is ROAS?

ROAS stands for return on ad spend, sometimes written as return on advertising spend. It tells you how much revenue your ads generate for every unit of currency you spend on them. A ROAS of 5 means each euro or dollar of ad spend brings in five in revenue.

You will see ROAS written in three ways. They mean exactly the same thing.

ROAS is an efficiency measure for advertising. It says nothing about the cost of goods, shipping, returns or the hours your team puts into a campaign. A high ROAS is a good sign, but it is not proof that a campaign makes money. That gap between revenue and profit runs through everything below.

The ROAS formula, with a worked example

You calculate ROAS by dividing the revenue you attribute to a campaign by what the campaign cost. For a percentage, multiply the result by 100.

ROAS = revenue from ads ÷ ad spend

Google uses the same arithmetic in its Google Ads Help article on Target ROAS: 5 in sales divided by 1 in ad spend, times 100%, is a target ROAS of 500%.

How to calculate ROAS

Take one campaign and one period, such as last month. Add up the revenue your conversion tracking attributes to that campaign, excluding VAT or sales tax. Add up what you paid the platform for the same campaign over the same period. Divide the first number by the second. That is your ROAS for that campaign and period, and it only compares fairly with other numbers calculated the same way.

Worked example

Say an online store selling premium coffee equipment spends EUR 5,000 on Google Ads in a month. Conversion tracking attributes EUR 20,000 in revenue to those ads, excluding VAT. The gross margin, what is left of revenue after product cost, shipping and payment fees, is 35%.

• ROAS: EUR 20,000 ÷ EUR 5,000 = 4, or 400%.
• Gross profit: 35% of EUR 20,000 = EUR 7,000.
• Profit after ad spend: EUR 7,000 - EUR 5,000 = EUR 2,000.

That is EUR 2,000 left from EUR 20,000 in revenue, or 10%, before salaries, software and rent. Respectable, but a long way from the “four times your money” the ROAS seems to promise. At the same ROAS with a 20% margin, the campaign would lose money.

Run your own numbers in the calculator. The defaults match the example.

ROAS, ACOS and the share of revenue spent on ads

Amazon Ads reports the same relationship upside down. ACOS, advertising cost of sales, divides ad spend by ad revenue and shows the result as a percentage, so a ROAS of 4 equals an ACOS of 25%. Amazon Ads describes ROAS as the inverse of ACOS: both measure the same result in a different format.

ACOS = ad spend ÷ revenue from ads × 100%

The percentage view has one practical advantage: you can hold it straight against your margin. As long as ACOS stays below your gross margin, something is left after ad spend. In the coffee example, a 25% ACOS against a 35% margin leaves exactly the 10% of revenue calculated above.

What counts as revenue and ad spend

The formula is simple. The debate is about what goes above and below the line. Agree on one definition and use it everywhere: in your spreadsheet, in your reports and in the conversion value you send to your ad platforms.

For revenue, use the amount excluding VAT or sales tax, because that money is never yours. The difference is larger than it looks: with 21% VAT, as in the Netherlands, a store that sends order values including VAT sees a ROAS of 4 where the real figure is 4 ÷ 1.21 = 3.31. Subtract returns and cancellations where you can measure them, since an ad platform usually keeps counting a returned order as a sale. Leave out shipping fees the customer pays if you also leave them out of your margin.

For cost, include at least the media spend you pay Google or Meta. If you want to know what advertising really costs, add your agency fee and tools too. That gives a lower ROAS, but a more honest one. State in your reports which version you use, so nobody compares two different numbers.

What is a good ROAS?

A good ROAS is one above your own break-even ROAS, and ideally above your target ROAS. There is no universal number. The same 400% is profitable at a 40% margin and loss-making at a 20% margin, so measure your campaigns against your own margin.

You will often read that “4:1 is a good ROAS”. Figures like that average across industries, margins and measurement methods, and say little about your business. That is why we deliberately give no benchmark here. What does help is knowing which factors decide the ROAS you need.

So is a 3.8 ROAS good? At a 35% margin it clears the break-even line of 2.86 and makes money. At a 25% margin the line sits at 4, and the same 3.8 loses money on every sale. Is a ROAS of 10 good? Usually, but check where it comes from. If the campaign mostly reaches people who would have bought anyway, you are paying for revenue you already had.

The break-even ROAS formula

Your break-even ROAS is the ROAS at which gross profit exactly covers ad spend: no profit, no loss. One division gets you there.

Break-even ROAS = 1 ÷ gross margin

At a 35% gross margin, that is 1 ÷ 0.35 = 2.86, or 286%. The coffee equipment store, at 400%, clears the line comfortably. At a 25% margin the line sits at 4, at 50% it drops to 2. The chart shows how quickly the bar rises as margin falls.

The biggest risk is the margin you plug in. Use your real gross margin per sale: revenue excluding VAT, minus product cost, shipping and packaging, payment fees and an average for returns. Anyone who uses the margin on the price tag almost always underestimates their break-even ROAS. If your products have very different margins, calculate per product group. One average across the whole range hides exactly the products you lose money on.

A stubborn misconception is that a ROAS of 1, or 100%, is break-even. At 1 you get your ad spend back as revenue, but you have not paid for the goods yet. Meta also calls a ROAS goal of 1.00 “break even”, in the sense of purchase value equal to spend. For your profit, the real break-even point is 1 divided by your margin.

Target ROAS: how to set your goal

Your target ROAS is the ROAS you need to keep the profit you want after paying for ads. You find it by subtracting your desired profit from your margin.

Target ROAS = 1 ÷ (gross margin - desired profit after ad spend)

Both percentages are shares of revenue. Take the store with a 35% margin. If it wants 10% of revenue left as profit after ads, advertising can take at most 25% of revenue. Its target ROAS is 1 ÷ 0.25 = 4, or 400%, which is exactly what the campaign delivers. The table shows break-even and target ROAS for five margins and three profit goals.

The table also shows why advertising thin-margin products is so hard. At a 20% margin and a 15% profit goal, you need a ROAS of 20. Hardly any campaign that has to find new customers gets there. At that point the question is not how to raise ROAS, but whether paid ads are the right channel for those products at all.

Target ROAS in Google Ads

In Google Ads, you set the goal with the Target ROAS bid strategy. Google predicts the value of a possible conversion in each auction and bids higher where the expected value is higher, aiming to keep your average conversion value per unit of cost equal to your target. From June 2026, Google Ads labels the strategy Target ROAS instead of Maximize conversion value with a Target ROAS. During the transition you may see both names, and the bidding behaviour stays the same.

For Search and Shopping campaigns, Google requires at least 15 conversions in the past 30 days, and your conversions need values. You find your historical ROAS in the Conv. value/cost column: multiply it by 100 for the percentage. Google also warns that a target set too high may limit the traffic your ads get, and advises leaving the most recent conversion delay period out of your evaluation.

In practice: start near your current ROAS, not at the number you would like to see. Raise the target step by step and give each change one to two conversion cycles, as Google itself recommends. If you want more volume, lower the target slightly so the strategy can enter more auctions.

ROAS goal in Meta

In Meta Ads Manager, the equivalent setting is the ROAS goal. You enter it as a multiplier between 0.001 and 1,000: a goal of 1.15 means you expect around EUR 115 in purchase value for every EUR 100 you spend. In its best practices for the ROAS goal, Meta recommends starting 10 to 20% below your average ROAS, and says the system works best when an ad set gets at least 50 to 100 conversions a week.

Meta describes anything above 1.00 as profit. That is only true at a 100% margin. A goal of 1.15 at a 35% margin loses money on every sale, so set the goal above your own break-even ROAS.

ROAS for lead generation

If you sell services, revenue arrives weeks later and outside your ad account. You can still work with ROAS by giving each enquiry a value: the average gross profit of a new client multiplied by the share of enquiries that become clients. If a client brings in EUR 6,000 in gross profit on average and one in five enquiries becomes a client, an enquiry is worth EUR 1,200. If you prefer to steer on cost per enquiry, work with a target CPA instead. How that plays out in search engine advertising is covered there.

For service businesses, this is often where the biggest gain is. What counts is not the number of enquiries but their quality, and what a new client costs you in the end. A campaign with fewer, better enquiries looks worse on paper and earns more in practice.

How to check ROAS in Google Ads, GA4 and Meta

Every platform uses the same ROAS formula, but with its own revenue figure. That is why the same campaign often shows three different numbers in Google Ads, Google Analytics 4 and Meta. All three do the maths correctly. They attribute a sale to an ad in different ways.

GA4 only shows ad costs if your property is linked to Google Ads or you import cost data. Google notes in its help article on the All channels report that Google Analytics and Google Ads attribute key events differently, so expect gaps between the two. Meta’s figure follows the attribution setting of your ad set, and where browser or device signals are missing, part of it can be modelled rather than observed.

Keep two things in mind when you read these numbers. Google Ads reports conversions by the date of the search, not the date of the purchase. According to the Google Ads Help on conversion lag, that can make ROAS for the most recent days look lower than it will end up. And each platform credits a sale to its own ads. Add up the revenue in Google Ads and Meta, and you can end up above what your store actually sold. So compare total store revenue with total ad spend every month. That blended ROAS across all channels is the number your accountant will recognise.

ROAS vs ROI vs POAS

ROAS measures revenue per unit of ad spend, POAS measures gross profit per unit of ad spend, and ROI measures net profit on your total investment. The closer a metric gets to profit, the better it describes your business, and the more data you need to calculate it.

The difference is clearest with products on different margins. Take three product groups that each get EUR 1,000 in ad spend and each bring in EUR 4,000 in revenue. All three have a ROAS of 4. Only the margin differs: 50%, 35% and 20%.

On ROAS the three groups look identical, and a bid strategy that optimises for revenue treats them that way. On profit, the first group keeps EUR 1,000 after ads, the second EUR 400 and the third loses EUR 200. For the full picture, read what POAS is and how to steer on it. How ROAS relates to the wider ROI of your marketing has its own article.

You can steer on profit inside Google Ads too. If you send cart data with your purchase conversions and your product costs are in Merchant Center, Google Ads also reports gross profit per campaign, according to its help article on conversions with cart data. Some stores send margin instead of revenue as the conversion value, which turns Target ROAS into a profit target in practice. That only works with accurate product costs. With outdated cost prices, you steer very precisely in the wrong direction.

How to improve ROAS

ROAS is a fraction, so you improve it in two ways: more value per unit of spend, or less spend for the same value. It helps to take the fraction apart.

ROAS = conversion rate × average order value ÷ cost per click

Say the coffee equipment store pays EUR 1.25 per click, 2.5% of visitors place an order and the average order value is EUR 200. Then ROAS is 0.025 × 200 ÷ 1.25 = 4. Each of those three numbers is a lever, and the biggest gains rarely sit inside the ad account itself.

Improve what happens after the click

If your conversion rate rises from 2.5% to 3.5% at the same cost per click, ROAS rises from 4 to 5.6. That takes a landing page that matches the ad, loads fast, earns trust and makes the next step easy. Our guide to conversion rate optimisation shows how. A better landing page pays twice, because landing page experience also feeds into your Quality Score in Google Ads.

Raise the value of each order

A higher average order value lifts ROAS without buying more clicks. Think of bundles, a free shipping threshold just above your current average, or a sensible add-on in the cart. Make sure the extra revenue carries margin too, or you only move the problem.

Cut wasted spend

Check the search terms report in Google Ads every week and exclude queries that never convert. Separate brand campaigns so their high ROAS does not flatter the rest. Group campaigns by margin band rather than by brand or category, and stop advertising products whose margin can never clear the break-even ROAS.

Test instead of guessing

Do not change five things at once. Test one ad, one landing page or one target at a time, and judge the result after a full conversion cycle. In Google Ads, Save as experiment lets you run a changed bid strategy next to your current settings first. That way you know what works instead of assuming it.

When a lower ROAS earns more

The goal is profit in euros, not the highest possible ratio. Say the coffee equipment store spends EUR 2,500 at a ROAS of 5: EUR 12,500 in revenue, EUR 4,375 in gross profit at a 35% margin, EUR 1,875 left after ads. It lowers its target, spends EUR 5,000 and lands at a ROAS of 4: EUR 2,000 left. The ratio fell and the profit rose.

The reason sits in the extra spend. The second EUR 2,500 brought in EUR 7,500 in revenue, a ROAS of 3 on the extra money, still above the break-even line of 2.86. Google Ads Help gives the same advice from the other side: lower the target ROAS gradually when you want more conversion volume. Keep going as long as the euros left after ad spend grow, and stop once the extra budget returns less than your break-even ROAS.

Common ROAS mistakes

These are the mistakes we see most often when we take over an ad account:

• Calculating with revenue including VAT, which makes ROAS look higher than it is.
• Leaving returns in, even though in some categories they are a large share of revenue.
• Judging brand campaigns and new-customer campaigns as one.
• Pausing a campaign on yesterday’s numbers while conversions are still coming in.
• Adding up the ROAS from Google Ads and Meta, forgetting that both claim the same sale.
• Using one target ROAS across the whole range while margins differ per product group.
• Chasing the highest possible ROAS while the profit in euros stays flat.
• Steering on ROAS alone and losing sight of how many new customers you win, and what they are worth.

Sometimes the honest answer is that improving ROAS is not the next step. If a campaign with a healthy margin, good ads and a sound bid strategy still cannot clear break-even, the problem usually sits earlier, in the message or the website. Fixing that pays back more than extra budget.

How we help

Viralistic is a strategic digital partner in Amsterdam, founded and led by Marrallisa Kreijkes. Our marketing starts organic. Before any money goes into ads, we check the foundation: a clear message built on your brand script, a fast website that turns visitors into enquiries or orders, measurement you can trust, and visibility in Google and in AI answers. As long as that foundation leaks, advertising mostly raises your costs.

When the foundation is healthy and you want to grow with Google Ads or Meta Ads, we do the maths with you first. The ROAS formula takes one line; deciding which revenue, which costs and which margin belong in it is where campaigns make or lose money. We set up conversion values so your ROAS matches your books, work out break-even and target ROAS per product group, and for service businesses we track what matters: the number of enquiries, their quality and the cost of a new client. Then we test broadly, review the numbers with you and decide together where more budget goes. A person checks every report, also when AI helped. Read more about our marketing approach and about Google Ads management.

Frequently asked questions

What does ROAS stand for?

ROAS stands for return on ad spend, also called return on advertising spend. It measures how much revenue your ads bring in for every unit of currency spent on them. A ROAS of 4, written as 4:1 or 400%, means four euros or dollars of revenue per one spent. It is a revenue metric, so always read it next to your gross margin.

Is ROAS calculated on profit or revenue?

On revenue. The standard ROAS formula divides the revenue attributed to your ads by ad spend, before product costs, shipping or returns. That is why a ROAS of 4 can still lose money at a 20% margin. For the same ratio on profit, divide gross profit by ad spend instead. That metric is POAS, profit on ad spend.

How is ROAS calculated in digital marketing?

Divide the revenue attributed to your ads by the ad spend for the same campaign and period. EUR 20,000 in revenue from EUR 5,000 in ad spend gives a ROAS of 4, or 400% when multiplied by 100. Use revenue excluding VAT and subtract returns where you can. Google Ads, GA4 and Meta each attribute sales differently, so their figures differ.

What does a 2:1 ROAS mean?

A 2:1 ROAS means every euro or dollar of ad spend brought in two in revenue: a ROAS of 2, or 200%. Whether that is profitable depends on your margin. At a 50% gross margin, 2:1 is exactly break-even. Above a 50% margin it makes money; below it, every sale costs you, because the product still has to be paid for.

Is a 3.8 ROAS good?

A 3.8 ROAS is good when your gross margin is above about 26%, because 1 ÷ 3.8 is 0.26 and that margin is your break-even point. At a 35% margin, 3.8 leaves roughly 9% of revenue after ad spend. At a 20% margin it loses money. Check whether brand campaigns, which reach people already looking for you, inflate the figure.

How do you check ROAS in Google Ads?

Add the Conv. value/cost column to your campaigns table via Modify columns, under Conversions. Multiply the number by 100 to get ROAS as a percentage, the format Google Ads uses for Target ROAS. With Target ROAS bidding, the bid strategy report also shows Actual ROAS. Leave out the most recent days, because conversions are reported by search date.

What is a good ROAS for Google Ads and Meta Ads?

The same rule applies on both: a good ROAS clears your break-even ROAS, 1 divided by your gross margin. The two channels still differ. Google Search reaches people who are already searching, so its ROAS is often higher. Meta reaches people who were not looking yet, where a lower ROAS can still win new customers. Set a target per channel.

What is the difference between ROAS and ROI?

ROAS divides revenue from ads by ad spend. ROI divides net profit by the total investment, including product costs, staff and other expenses. A campaign can show a ROAS of 400% and still have a negative ROI when margins are too thin to cover ad spend and everything else. Use ROAS to steer campaigns and ROI to judge your marketing as a whole.

How do you calculate ROAS in Excel or Google Sheets?

Put revenue from ads in one column and ad spend in the next, then divide: =B2/C2 gives ROAS as a ratio, and formatting the cell as a percentage shows it the way Google Ads does. Add a gross margin column and =1/D2 returns the break-even ROAS for each row. Compare the two columns to see which campaigns make money.