Last updated: 2026-07-02

What ROAS measures

Return on ad spend, or ROAS, answers one question: for every unit of currency put into advertising, how much revenue came back? It is the ratio of revenue attributed to a campaign to the amount spent on that campaign. A ROAS of 4 means $4 of revenue for every $1 of spend; the same figure is often written as 4x or as 400%.

ROAS is popular because it is quick to read and easy to compare across campaigns, channels, and time periods. It is not a profit measure, though. It looks only at revenue against ad spend and says nothing about the cost of the product, shipping, or overhead. A campaign can post an eye-catching ROAS and still lose money once those costs are counted, which is why this calculator also reports profit and a break-even ROAS.

The formula

ROAS divides campaign revenue by campaign spend:

The result is a pure ratio. Multiply by 100 to read it as a percent:

The raw profit on the campaign — before product and operating costs — is simply the difference between the two inputs:

Worked example: a paid social campaign

A store runs a two-week paid social campaign. The ads are credited with $8,000 in sales, and the store paid $2,000 in media and platform fees over the same window.

ROAS divides revenue by spend:

So the campaign returned $4.00 of revenue for every $1.00 spent, or 400%. The gross figure on the campaign is:

That $6,000 is revenue minus ad spend only. It is not the money the business keeps, because the $8,000 of revenue still has to pay for the goods sold. That gap is where break-even ROAS comes in.

Break-even ROAS

ROAS looks healthy at 4, but whether the campaign actually made money depends on the margin on what was sold. The break-even ROAS is the point at which revenue just covers ad spend after the product cost is accounted for. It depends only on the contribution margin — the share of each revenue dollar left after the cost of the product:

Suppose the store keeps 50% of revenue as contribution margin. Then:

The campaign needs a ROAS of at least 2 to break even. It posted a ROAS of 4, comfortably above that threshold, so it added profit. Had the margin been only 20%, the break-even ROAS would jump to 1 / 0.20 = 5 — and the same 4x campaign would have lost money despite its strong headline number.

A few margin-to-threshold pairs show how sharply the requirement moves:

Thin margins demand a high ROAS; fat margins let a campaign turn a profit at a much lower return.

ROAS versus ROI

ROAS and return on investment are often confused. ROAS compares revenue to ad spend. ROI compares net profit to total cost. Because ROAS ignores the cost of goods and overhead, it always reads higher than ROI for the same campaign. Treating a strong ROAS as if it were a strong ROI is the most common way advertisers overestimate how profitable a campaign really is. Reading ROAS next to the break-even ROAS closes most of that gap: if ROAS clears the break-even line, the campaign is contributing profit; if it does not, the headline number is misleading.

Where the inputs come from

Two figures drive the result. Ad revenue is the sales credited to the campaign, which depends on the attribution window and model the ad platform or analytics tool uses — a longer window credits more sales. Ad spend should include everything paid to run the campaign: media cost plus any agency retainer or platform fee attributed to it. Understating spend or overstating attributed revenue both inflate ROAS, so keep the definitions of both inputs consistent when comparing one campaign to another.

To turn campaign economics into a per-customer view, pair this with the Customer Acquisition Cost (CAC) Calculator, which finds what it costs to acquire each customer, and the LTV:CAC Ratio Calculator, which weighs that cost against lifetime value.