ROI vs ROAS: What’s the Difference?
If you run any kind of paid advertising, you have probably seen both ROI and ROAS used to describe campaign performance. While the two metrics are related, they measure different things and serve different purposes. Confusing them — or using the wrong one at the wrong time — can lead to bad budget decisions and missed opportunities.
What Is ROI?
Return on Investment (ROI) measures the overall profitability of an investment after accounting for all costs. The formula is:
ROI = (Net Profit / Total Investment) × 100
ROI gives you the big picture. It factors in every expense — ad spend, product costs, shipping, labor, software subscriptions, agency fees — and tells you whether you ended up ahead or behind. A positive ROI means you made money. A negative ROI means you lost money.
What Is ROAS?
Return on Ad Spend (ROAS) measures how much revenue you generate for every dollar spent on advertising. The formula is:
ROAS = Revenue from Ads / Ad Spend
ROAS is typically expressed as a ratio or multiplier. A ROAS of 4.0 means you earned $4 in revenue for every $1 spent on ads. Unlike ROI, ROAS does not subtract costs like product manufacturing, fulfillment, or overhead — it only looks at revenue relative to ad spend.
Side-by-Side Comparison
| Feature | ROI | ROAS |
|---|---|---|
| Measures | Overall profitability | Revenue per ad dollar |
| Includes all costs | Yes | No (ad spend only) |
| Format | Percentage | Ratio or multiplier |
| Best for | Business-level decisions | Campaign-level optimization |
| Can be negative | Yes | Not typically (revenue ≥ 0) |
A Practical Example
Imagine you sell handmade candles online and run a Google Ads campaign:
- Ad spend: $2,000
- Revenue from ad-driven sales: $10,000
- Cost of goods sold (materials, packaging): $3,500
- Shipping costs: $800
- Payment processing fees: $300
ROAS: $10,000 / $2,000 = 5.0 (you made $5 for every $1 in ad spend)
ROI: Total costs = $2,000 + $3,500 + $800 + $300 = $6,600. Net profit = $10,000 − $6,600 = $3,400. ROI = ($3,400 / $6,600) × 100 = 51.5%
The ROAS of 5.0 looks impressive, but the true ROI of 51.5% gives a more honest picture of profitability after all costs are considered. A business that only tracks ROAS might scale a campaign that looks great on paper but barely breaks even when all costs are included.
When to Use Each Metric
Use ROAS when you need to evaluate and compare the efficiency of individual ad campaigns, ad groups, or channels. It helps you decide where to increase or decrease ad spend for maximum revenue.
Use ROI when you need to assess whether your overall marketing or business strategy is profitable. It is the metric stakeholders and investors care about because it reflects actual bottom-line impact.
The smartest approach is to track both. Use ROAS to optimize campaigns day-to-day, and use ROI to make bigger strategic decisions about budgets, pricing, and growth.
Calculate Your Numbers
Use our free ROI Calculator to measure the true return on any investment. For more context on what your results mean, check out what makes a good ROI or browse our full ROI Resources library.
Related: What Is ROI? | How to Calculate ROI | What Is a Good ROI?