ROAS Calculator (Return on Ad Spend)
Calculate ROAS, break-even ROAS, and profit from your ad spend, revenue, and margin. See whether your ads are actually profitable, not just positive.
What is ROAS?
ROAS stands for Return on Ad Spend — the revenue you earn for every dollar you spend on advertising. It is the single most common metric marketers use to judge whether a campaign is "working." A ROAS of 4× means every $1 of ad spend brought back $4 in revenue. The formula is simple:
ROAS = Revenue from Ads ÷ Ad Spend
The catch is that a high ROAS does not automatically mean you made money. Revenue is not profit. If your products carry thin margins, a 4× ROAS can still leave you underwater once the cost of goods is subtracted. That's why this calculator also computes your break-even ROAS and your actual profit after ad spend.
ROAS vs. profitable ROAS: break-even ROAS
Your break-even ROAS is the ROAS you need just to cover the cost of the goods you sold. It depends entirely on your product margin:
Break-even ROAS = 1 ÷ Product Margin
- At a 50% margin, break-even ROAS is 1 ÷ 0.50 = 2.0×.
- At a 40% margin, break-even ROAS is 1 ÷ 0.40 = 2.5×.
- At a 25% margin, break-even ROAS is 1 ÷ 0.25 = 4.0×.
Any ROAS above your break-even point is profitable; any ROAS below it loses money even though it still looks like a positive return. This is the number most advertisers forget to compute — they chase a "good" ROAS like 4× without checking whether 4× is even enough for their margins.
What is ACoS?
ACoS (Advertising Cost of Sales) is simply the inverse of ROAS, expressed as a percentage. It's the metric Amazon Ads reports by default. ACoS = Ad Spend ÷ Revenue × 100. A 4× ROAS is the same as a 25% ACoS — you spent 25 cents in ads for every dollar of revenue. Lower ACoS is better; higher ROAS is better; they describe the same relationship from opposite directions.
How to use this calculator
Enter your ad spend, the revenue those ads generated, and your product margin (gross profit as a percent of revenue, before ad costs). The calculator instantly returns your ROAS, the break-even ROAS you need to hit, your profit after ad spend, and your ACoS — and tells you plainly whether the campaign is actually profitable.
Worked example
Suppose you spend $1,000 on ads and they generate $4,000 in revenue on products with a 40% margin:
- ROAS = $4,000 ÷ $1,000 = 4.0×
- Break-even ROAS = 1 ÷ 0.40 = 2.5×
- Gross profit on that revenue = $4,000 × 40% = $1,600
- Profit after ad spend = $1,600 − $1,000 = $600
- ACoS = $1,000 ÷ $4,000 = 25%
Because 4.0× is comfortably above the 2.5× break-even, the campaign clears $600 in real profit. Drop the margin to 25% and break-even rises to 4.0× — that same 4.0× ROAS would now merely break even, netting $0 in profit. Same ads, same revenue, very different outcome: this is why margin belongs in every ROAS decision.
This tool measures the direct return on a given batch of ad spend. It does not account for fixed overhead, returns, shipping subsidies, repeat-purchase (lifetime) value, or attribution accuracy — real businesses often accept a lower ROAS on the first order because a customer buys again. Use it as a fast profitability check, not a full P&L.