What is ROI (return on investment)? Formula and examples

ROI (return on investment) is a profitability metric that shows how much net profit an investment generates compared with its cost, usually expressed as a percentage. In marketing it answers one question: did this campaign make more money than it cost? According to Nielsen’s 2025 Marketing ROI Blueprint, 85% of marketers say they can measure ROI, but only 32% measure it across traditional and digital channels together.

Updated: 17 October 20263 min read
Infographic comparing ROI and ROAS: ROI 120% vs ROAS 500% for the same campaign
Source: Marketer Coffee worked example; Google Economic Impact methodology

How do you calculate ROI?

You calculate ROI by dividing net profit from an investment by its cost and multiplying by 100. The standard formula is:

ROI = (gain from investment − cost of investment) ÷ cost of investment × 100%

In marketing, “gain” should be gross profit, not revenue, because the products you sell also cost money. “Cost” covers everything the campaign consumed: ad spend, agency fees, tools, creative production and staff time. A positive ROI means the campaign earned more than it cost; 0% means break-even; a negative ROI means a loss.

ROI example in USD

A worked example shows why ROI is always lower than ROAS for the same campaign. An online shop runs a Google Ads campaign for one month:

ItemValue
Revenue from the campaign20,000 USD
Cost of goods sold9,000 USD
Gross profit11,000 USD
Ad spend4,000 USD
Agency fee and tools1,000 USD
Total investment5,000 USD

ROI = (11,000 − 5,000) ÷ 5,000 × 100% = 120%. Each dollar invested returned 1.20 USD of net profit. The same campaign has a ROAS of 20,000 ÷ 4,000 = 500%, which looks far better because it ignores product costs and fees.

What is a good marketing ROI?

A good marketing ROI is any value that beats your cost of capital and your other options, and it differs strongly by channel. Published benchmarks give a sense of scale:

  • Google’s Economic Impact methodology assumes advertisers earn about 2 USD of profit per 1 USD spent on Google Ads, based on Hal Varian’s 2009 research.
  • Google’s estimate rises to about 8 USD of profit per 1 USD when it adds the value of organic clicks that come with paid visibility.
  • Litmus’s 2025 State of Email report found that 35% of marketing leaders get 10 to 36 USD back for every 1 USD spent on email, and another 30% get 36 to 50 USD.

Treat these as ranges reported by the platforms themselves, not as targets. In my projects I set the ROI target from the client’s margin: a shop with a 20% margin needs far more revenue per dollar than a SaaS company with 80% margins.

ROI vs ROAS, CPA and LTV

ROI differs from its neighbours because it is the only one of them that measures profit after all costs. The table compares them.

MetricWhat it measuresFormula
ROINet profit vs total investment(gain − cost) ÷ cost
ROASRevenue vs ad spend onlyrevenue ÷ ad spend
CPACost of one conversionspend ÷ conversions
LTVValue of a customer over timeavg order value × purchases × margin

ROAS is better for daily bid decisions in ad platforms, while ROI is the number a CFO uses to decide whether marketing gets more budget.

ROI in SEO and paid campaigns

ROI in SEO is harder to calculate than in ads, because costs come first and returns build up over months. I measure SEO ROI over 12 to 24 months, counting organic conversions valued at margin, against content, technical work and link costs. The same model works for Meta Ads and other PPC channels, as long as attribution windows are the same.

Pro tip: Import product margins into your analytics or ad account and report profit, not revenue. Smart bidding optimised for profit regularly cuts spend on bestsellers with thin margins, which raises ROI even when ROAS falls.

Frequently asked questions about ROI

What is the ROI formula?

ROI equals gain from the investment minus its cost, divided by the cost, multiplied by 100%. For example, 11,000 USD of gross profit on a 5,000 USD investment gives an ROI of 120%.

What is the difference between ROI and ROAS?

ROI measures net profit after all costs, while ROAS only divides revenue by ad spend. A campaign can have a 500% ROAS and still a much lower ROI once product costs and fees are counted.

What is a good ROI in marketing?

A good marketing ROI is positive and higher than the return from your other options. Google's own methodology assumes about 2 USD of profit per 1 USD spent on Google Ads, while email often reports higher ratios.

Can ROI be negative?

ROI is negative when the investment costs more than it earns. A result of minus 20% means the campaign lost 20 cents for every dollar invested.

Related terms

International SEO · AI SEO (GEO)

Grow in every market, and get cited by AI

ROI looks different in every market, because margins, CPCs and buying habits differ between Poland, Germany and the US. I build international SEO and AI search strategies around the profit each market can actually deliver, not around traffic alone.

I help SaaS and e-commerce brands win organic traffic across Europe and the US, and get their brand recommended in ChatGPT, Gemini, Perplexity and Google AI Overviews. Every project starts with a free audit of your site, your markets and your visibility in AI answers.

Write to Adrian

Have a question about this term or your SEO?

Send a short message about your website, the markets you sell in and what you want to achieve. You get a reply from me, not from a sales team.

  • Free preliminary SEO and AI visibility audit
  • Strategy for international and multilingual markets
  • Reply within one business day
Book a free call
Adrian Dąbrowiecki

Write to Adrian

Adrian Dąbrowiecki · Marketer Coffee

Tell me about your site and your goals. I usually reply within one business day.