ROAS Calculator

Background.

Two online shops each spend $10,000 on ads in a month, and each is credited with $40,000 of sales. Both report a ROAS of 4×. The first sells at a 60% gross margin, so its $40,000 of sales carries $24,000 of gross profit and leaves $14,000 after paying for the ads. The second sells at 20%, makes $8,000 of gross profit and is $2,000 down once the ad bill is paid. Same ratio, opposite results.

Return on ad spend is revenue divided by what the advertising cost, and it is the number every ad platform puts at the top of its dashboard. It is excellent for comparing one campaign, audience or channel with another inside the same business. What it cannot say on its own is whether the advertising made money, because revenue is not profit. That needs a second number: the ROAS at which the gross profit on the sales exactly pays for the ads. At a 60% margin that break-even point is 1.67×; at 20% it is 5×, which is why the second shop's 4× is a loss.

Enter your gross margin alongside revenue and spend and you get that break-even line, the revenue your spend needs to reach it, and the gross profit left once the ads are paid. The same inputs also run in reverse for planning: the revenue a budget must bring in at a target ROAS, or the budget a revenue goal can support.

What is roas calculator?

Return on ad spend, ROAS, is the revenue attributed to advertising divided by the cost of that advertising. The Marketing Accountability Standards Board's Universal Marketing Dictionary defines it as sales attributable to ads divided by the cost of ads. It is written in several ways that all mean the same thing: Google Ads states targets as percentages, so $5 of sales per $1 of spend is 500%; Amazon Ads uses ratio notation such as 2:1; Google Analytics reported it as a plain ratio. ROAS differs from return on investment in its numerator: ROAS uses revenue, while ROI uses net profit, so a campaign can show a high ROAS and a negative ROI. Break-even ROAS is the reciprocal of gross margin, the revenue multiple at which gross profit on the attributed sales just covers the media cost.

How to use this calculator.

1. 01Choose what to solve for. ROAS measures a campaign that has run; Revenue tells you what a planned budget must bring in at a target ratio; Ad spend tells you the budget a revenue goal supports at a ratio you can sustain.
2. 02Enter attributed revenue as your ad platform or analytics tool reports it for the same campaigns and dates, excluding sales tax and any shipping charged to the customer. For lead generation, enter the money value you assign to the leads.
3. 03Enter ad spend as media cost only. Agency fees, creative production and salaries belong in a fuller marketing return calculation, not in ROAS.
4. 04When planning, enter ROAS as a ratio: 4 means 4×, the same as 400% or 4:1.
5. 05Enter gross margin as revenue minus cost of goods, divided by revenue, in percent. Use gross margin, not markup and not net margin; a product bought for $55 and sold for $100 has a 45% margin even though its markup is 82%.
6. 06Compare ROAS with break-even ROAS and look at gross profit after ads. A negative profit means the campaign did not cover the cost of the goods it sold plus its own media bill.

The formula.

The core identity is ROAS = R ⁄ S, where R is the revenue attributed to the advertising and S is the ad spend. Rearranged, R = ROAS × S and S = R ⁄ ROAS, which is how the planning modes work. ROAS as a percent is the ratio multiplied by 100.

The profitability outputs bring in the gross margin m, written as a fraction (45% is 0.45). Every dollar of attributed revenue carries m dollars of gross profit, so the gross profit left after the ads is R × m − S. Setting that to zero and dividing by S gives the break-even condition R ⁄ S = 1 ⁄ m: break-even ROAS is the reciprocal of the margin. Break-even revenue is the same threshold in dollars for the spend you entered, S ⁄ m. A 45% margin gives 2.22×; 30% gives 3.33×; 70% gives 1.43×; at 100%, a product with no cost of goods, break-even is exactly 1×, where revenue merely equals spend.

Because break-even ROAS is 1 ⁄ m, it is very sensitive to thin margins. Halving the margin from 30% to 15% does not add a little to the required ROAS; it doubles it, from 3.33× to 6.67×. Margin is accordingly the input most worth checking. A margin of zero has no break-even at all, since no amount of revenue covers the ads, and a margin above 100% is impossible, so both are refused.

Two limits follow from the definitions. The threshold is a gross one: it covers cost of goods and media, but not fulfilment, payment processing, returns, customer service or overheads, so the ROAS a business actually needs is higher. And R is whatever the attribution model credits to the ads. If the model claims sales that would have happened anyway, ROAS and gross profit after ads are overstated together, and no rearrangement of the formula will reveal it.

A worked example.

Frequently asked questions.

References& sources.

1. [1]MASB / Common Language in Marketing Project — Universal Marketing Dictionary, entry "Return on Ad Spend" (Common Language in Marketing Project, 2022; Universal Marketing Dictionary Project, 2024): "Return on Ad Spend (%) = Sales Attributable to Ads ($) / Cost of Ads ($)", plus the note that early-2020s calculations "often included non-advertising-driven sales, inflating results" and that correctly calculated ROAS and iROAS are identical. Retrieved 2026-07-29.
2. [2]MASB / Common Language in Marketing Project — Universal Marketing Dictionary, entry "Return on Investment": "Return on investment (%) = Net profit ($) ÷ Investment ($) x 100", citing Farris, Bendle, Pfeifer & Reibstein (2010). Cited here for the revenue-versus-profit contrast with ROAS. Retrieved 2026-07-29.
3. [3]Farris, Paul W.; Bendle, Neil T.; Pfeifer, Phillip E.; Reibstein, David J. — Marketing Metrics: The Definitive Guide to Measuring Marketing Performance, 3rd ed., Pearson Education (ISBN 978-0-13-705829-7). Chapter 9 "Advertising Media and Web Metrics" and Chapter 10 "Marketing and Finance" (Net Profit, Return on Sales). Print reference — no free full text; edition, ISBN and chapter structure verified against the publisher's sample-pages PDF.
4. [4]Google Ads Help — "About Target ROAS bidding": target ROAS is "the average conversion value (for example, revenue) you'd like to get for each dollar you spend on ads", worked as "$5 USD in sales ÷ $1 USD in ad spend x 100% = 500% target ROAS". Retrieved 2026-07-29.
5. [5]Google Ads Help — "About return on investment (ROI)": "ROI is the ratio of your net profit to your costs", worked on a $200 product costing $100 to produce, six units sold on $200 of ad spend: ($1200 − $800) / $800 = 50%. The same campaign is a 600% ROAS. Retrieved 2026-07-29.
6. [6]Amazon Ads — "What is Return on Ad Spend? How to Calculate ROAS" (Advertising Library guide): ROAS is "the amount of revenue from an ad campaign, divided by the amount spent on the campaign itself"; "A 2:1 ROAS ratio … would mean a brand is making $2 to every $1 of ad spend"; ROAS is campaign-specific whereas ROI "takes much more of advertising spends or total advertising cost into account". Retrieved 2026-07-29.
7. [7]Google Analytics Help — "[UA] About the Cost Analysis Report": ROAS is calculated as "((ecommerce revenue + total goal value) / advertising cost)" — a bare ratio, with non-transactional goal value included in the numerator. Retrieved 2026-07-29.
8. [8]Microsoft Learn / Xandr — Online Advertising and Ad Tech Glossary (document date 2025-10-22). Cited for a documented absence: the glossary carries CPM, CPC, CPA, vCPM, eCPM, eCPC and eCPA but contains no ROAS entry, because ROAS is an advertiser-side outcome measure rather than an ad-serving pricing model. Retrieved 2026-07-29.