--- title: "ACOS Calculator: ACOS to ROAS and Break-even ACOS" description: "Free ACOS calculator: enter ad spend and ad sales for your ACOS and ROAS, convert one to the other, and find your break-even ACOS and TACOS." canonical: "https://www.productmetrics.io/acos-calculator" pageType: feature language: en publisher: "Product Metrics" dateModified: 2026-10-15 --- > Content index: https://www.productmetrics.io/llms.txt # ACOS calculator Enter your ad spend and ad sales to get your advertising cost of sales (ACOS) and ROAS. Add a contribution margin to see the break-even ACOS and whether your ads earn a profit, and total revenue for TACOS. _ACOS and ROAS use sales as entered, the basis of your ad platform. The margin applies to sales excl. VAT, so enter your VAT rate if sales include it._ ## Every step behind the numbers, worked through for the start values. Illustrative data. An example shop spent €2,000.00 on ads, which the ad platform credits with €8,000.00 of sales (excl. VAT, so the VAT rate is 0%). Its contribution margin is 30% and its total revenue €20,000.00. | Step | Calculation | Result | | --- | --- | --- | | ACOS | €2,000.00 ÷ €8,000.00 | 25% | | ROAS | €8,000.00 ÷ €2,000.00 | 4 | | Break-even ACOS | 30% ÷ (1 + 0%) | 30% | | Break-even ROAS | 1 ÷ 30% | 3.33 | | Break-even target ROAS | 3.33 as a percentage | 333% | | Profit on ad sales | €8,000.00 × 30% − €2,000.00 | €400.00 | | TACOS | €2,000.00 ÷ €20,000.00 | 10% | Every €100.00 of ad sales leaves €30.00 of margin to pay for the ads. The ads cost €25.00 of that, an ACOS of 25%, so €5.00 per €100.00 is left: €400.00 across €8,000.00 of ad sales. The same ads are 10% of all revenue. ## ACOS to ROAS and back, the same number turned round. ROAS is 100 divided by the ACOS in per cent, and ACOS is 1 divided by ROAS. Do not subtract from 100: an ACOS of 25% is a ROAS of 4, not 0.75. | ACOS | ROAS | Target ROAS in Google Ads | | --- | --- | --- | | 10% | 10 | 1,000% | | 20% | 5 | 500% | | 25% | 4 | 400% | | 40% | 2.5 | 250% | | 50% | 2 | 200% | | 100% | 1 | 100% | Google Ads asks for a target ROAS as a percentage: an ACOS of 20% is a ROAS of 5, which you enter as a target of 500%. ## Four numbers, and the decision each one informs. - **ACOS.** Ad spend ÷ ad sales: the share of ad sales spent on the ads. Lower is better. Decision: whether the ads cost less than the margin the sales leave. - **ROAS.** Ad sales ÷ ad spend: the sales per €1.00 of ad spend, and the inverse of ACOS. Decision: the same as ACOS, in the metric Google Ads bids on. - **Break-even ACOS.** Your contribution margin as a percentage: the ACOS at which the ads use up all the margin on the sales they brought. Below it ads earn a profit, above it they lose money. - **TACOS.** Ad spend ÷ total revenue, not only ad sales. Decision: how much of the whole shop’s revenue goes on ads, including sales that came without them. - [ACOS vs ROAS](https://www.productmetrics.io/glossary/acos-vs-roas) - [ROAS](https://www.productmetrics.io/glossary/roas) ## What ACOS cannot tell you, and what to read next to it. - **Which products earn their spend.** Break-even ACOS is the margin, and margins differ per product. One account-wide ACOS target loses money on low-margin products and holds back high-margin ones. Product Segmentation reads each product’s volume and return, ROAS or POAS. - **What the ads caused.** ACOS counts the sales your ad platform credits to the ads. It does not show which of those sales would have happened anyway. TACOS puts the same spend against all revenue. - **How accurate the margin is.** The break-even ACOS is only as good as the margin you enter. Use the margin left after product cost and the variable costs of an order, not the markup. - [How Product Segmentation works](https://www.productmetrics.io/product-segmentation) - [Break-even ROAS calculator](https://www.productmetrics.io/break-even-roas-calculator) ## ACOS questions, answered. ### How do you calculate ACOS? Divide ad spend by ad sales and show it as a percentage: €2,000.00 ÷ €8,000.00 = 25%. Use the sales your ad platform credits to the ads, not the shop’s total revenue. Divide by total revenue and you get TACOS, which is 10% for the example. ### How do you convert ACOS to ROAS? Divide 100 by the ACOS in per cent: 100 ÷ 20 = 5. To go back, divide 1 by the ROAS: 1 ÷ 5 = 20%. In Google Ads, enter that ROAS as a target ROAS of 500%. ### What is a good ACOS? It depends on your margin, so there is no universal number. Ads earn a profit while the ACOS stays below the break-even ACOS, which is the contribution margin as a percentage. At a 30% margin that is 30%, which is a ROAS of 3.33. A good ACOS is below that line by enough to cover fixed costs and the profit you want to keep. ### What is the difference between ACOS and TACOS? ACOS divides ad spend by the sales the ads are credited with. TACOS divides it by total revenue, including sales that came without the ads, such as organic search, email or returning customers. With €2,000.00 of ad spend, €8,000.00 of ad sales and €20,000.00 of revenue, ACOS is 25% and TACOS 10%. ### Is ACOS the same as target ROAS in Google Ads? No, but one converts into the other. Target ROAS is the ROAS you ask Google Ads to aim for, written as a percentage. An ACOS of 20% is a ROAS of 5, which is a target ROAS of 500%. ## Embed this calculator Paste this script tag into your own page to show the calculator there, with the same maths and no sign-up. It fits the width of your page, resizes with the calculator and follows the visitor’s light or dark setting. The script adds the calculator and a link to the full version under it. Keep the attribution link: it credits the calculator. `` ## Related pages. - [ACOS vs ROAS](https://www.productmetrics.io/glossary/acos-vs-roas): The difference between the two, with a table by margin. - [ROAS](https://www.productmetrics.io/glossary/roas): Revenue per €1.00 of ad spend, and what it leaves out. - [Break-even ROAS calculator](https://www.productmetrics.io/break-even-roas-calculator): The ROAS your products need, with returns, shipping and fees. - [Margin calculator](https://www.productmetrics.io/margin-calculator): Work out the margin to enter above. - [POAS calculator](https://www.productmetrics.io/poas-calculator): Profit per €1.00 of ad spend instead of revenue. - [Google Ads metrics calculator](https://www.productmetrics.io/ad-metrics-calculator): CTR, CPC, CPM and CPA from one set of numbers. - [Contribution margin](https://www.productmetrics.io/glossary/contribution-margin): The margin that sets the break-even ACOS. - [Product Segmentation](https://www.productmetrics.io/product-segmentation): Segment products by advertising clicks and return. ## See which products earn their ad spend, and which don’t. Product Metrics segments your products by advertising clicks and return against your target, then writes each segment to a Merchant Center label your campaigns use. - [Analyse your products for free](https://app.productmetrics.io/): Log in with Google, no credit card --- Published by Product Metrics (Berend Vrakking, founder). HTML version: https://www.productmetrics.io/acos-calculator