SEO ROI is the gross profit organic search brings in, minus what you spend on SEO, divided by that spend. This calculator works it out from the numbers you can find before you start: how many people search for your target keywords, where you expect to rank, how many visitors become leads and customers, and what a customer is worth. Two things most SEO ROI calculators leave out are built in here. Rankings take months to arrive, so traffic ramps up. And AI Overviews take clicks, so you can lower the click-through rate on the searches that show one.
| Month | Visits | Customers | Gross profit (cumulative) | SEO cost (cumulative) |
|---|
Organic click-through rate by position: three studies disagree
What is the SEO ROI formula?
The calculation chains five steps. Each one is a place where a forecast can go wrong, so it helps to see them separately:
| Step | Formula | Example (defaults above, at the target position) |
|---|---|---|
| Click-through rate after AI Overviews | CTR x (1 - AI Overview share x 58%) | 10.2% x (1 - 20% x 58%) = 9.02% |
| Organic visits | Search volume x CTR | 20,000 x 9.02% = 1,803 a month |
| Leads | Visits x visitor-to-lead rate | 1,803 x 1% = 18 a month |
| Customers | Leads x lead-to-customer rate | 18 x 5% = 0.9 a month |
| Gross profit per customer | Deal value x gross margin x years counted | $24,000 x 80% x 1 = $19,200 |
| ROI | (Gross profit - SEO cost) / SEO cost | Over 24 months, with the 9-month ramp: see the table in the calculator |
The calculator counts a customer's gross profit in the month they sign, which is the usual way to compare channels on payback. The ramp is a straight line: in a 9-month ramp, month 1 gets one ninth of the target traffic, month 9 gets all of it. Real rankings move in steps, but a straight line is closer to what happens than full traffic from day one.
Where do the click-through rates come from?
Click-through rate is the input that moves the answer most, and published studies give very different numbers for the same position:
- First Page Sage (2026 table): 39.8% at position 1, 18.7% at 2, 10.2% at 3, then 7.2%, 5.1%, 4.4%, 3.0%, 2.1%, 1.9% and 1.6% at position 10, as republished by OuterBox in May 2026. These are the defaults in the position menu.
- Backlinko: the number 1 result gets a 27.6% click-through rate and the top three get 54.4% of clicks, from Search Console data across 12 million queries (updated April 2025).
- GrowthSRC Media: position 1 fell from 28% to 19% and position 2 from 20.83% to 12.6% year over year, across more than 200,000 keywords from 30 sites, as AI Overviews spread (study, reported by Search Engine Journal in July 2025).
- Ahrefs: across 300,000 keywords, the top-ranking page had a 58% lower average click-through rate when an AI Overview was present, comparing December 2023 with December 2025 (published February 2026). The calculator applies that cut to the share of volume you mark as showing an AI Overview, at every position. Ahrefs measured it for the top result, so treat it as an approximation lower down.
For a forecast you will be held to, use the lower curve, or better, your own. In Google Search Console, filter Performance to queries where your average position is between 2.5 and 3.5 and read the click-through rate. Our CTR calculator does the arithmetic, and the zero-click search entry explains where the missing clicks go.
Why do most SEO ROI forecasts come out too high?
- They count branded searches. People searching your company name would find you anyway. Use only non-branded keywords in the volume field.
- They assume full traffic in month 1. Without a ramp, a 24-month ROI can look twice as good as it will be. Omnius, a SaaS SEO agency, says its projects see early results in 30 to 60 days, meaningful results at 4 to 8 months and significant results in months 9 to 12 (its guide); the default ramp is 9 months.
- They assume number 1 for every keyword. A new B2B site will hold a mix of positions. Pick the average you can defend, not the one you hope for.
- They use revenue, not gross profit. Margin matters: an 80% margin SaaS product keeps $0.80 of each dollar to pay back the SEO spend; a 40% margin service keeps half that.
- They ignore AI answers. Searches with an AI Overview send fewer clicks. Check your keywords in Google and set the share honestly.
- They forget the cost of keeping pages current. Pages lose rankings when competitors update theirs. Budget for refreshes in the monthly cost.
The opposite error is real too. Last-click attribution often credits a deal to a branded search or a direct visit when the buyer first found you through an organic article months earlier. The calculator counts only leads that convert from the organic visit, so it leans conservative on that side. For more on measuring this inside a SaaS company, see the ROI section of our SaaS SEO guide.
How do you pick the inputs?
| Input | Where to get it |
|---|---|
| Search volume | A keyword tool such as Ahrefs, Semrush or Google Keyword Planner; sum the US volume of the keywords in your plan. Our Ahrefs pricing guide and Semrush vs Ahrefs comparison help you choose a tool |
| Position | Look at who ranks now. If the top 10 is all large, well-linked sites, plan for positions 5 to 10 in year one |
| AI Overview share | Search your top 20 keywords in a private window and count how many show an AI Overview |
| Visitor to lead rate | Your current organic conversion rate from analytics. Our conversion rate calculator works it out per stage |
| Lead to customer rate | Your CRM: of last year's inbound leads, how many closed |
| Deal value and margin | Finance; use first-year contract value, not lifetime |
| Monthly SEO cost | Everything: people, writers, tools, links, design and development time |
Illustrative. With the defaults (20,000 searches, average position 3, 20% of searches with an AI Overview, 1% to lead, 5% to customer, $24,000 deals at 80% margin, $8,000 a month, 9-month ramp), SEO brings in about 1,800 visits, 18 leads and 0.9 customers a month at full traffic, pays back in month 8 and returns 80% over 24 months, at about $10,600 of SEO cost per customer. Move the average position to 5 and it does not pay back inside two years (a 24-month ROI of -10%). Raise the visitor-to-lead rate to 2% instead and it pays back in month 4. That is why the work on the page (a clear offer, a demo path that converts) matters as much as the ranking.
How does SEO ROI compare with paid channels?
Look at the "SEO cost per customer" figure and put it next to the same number for paid search and LinkedIn. Our CAC calculator works out cost per customer by channel, and the LTV to CAC calculator shows whether either one is worth scaling. SEO usually starts more expensive per customer and gets cheaper each month the pages keep ranking, because the cost does not rise with traffic the way ad spend does. Paid starts faster and stays at the same cost per click. For how organic search feeds pipeline in practice, see SEO for lead generation.
Where Growigami fits
Our AI search and SEO service writes the pages buyers and AI assistants look for at the decision stage, such as comparisons, alternatives and integrations, and reports organic leads and pipeline, not only rankings. If you are looking for a team to run SEO for a software company, our SaaS SEO agency page explains how we work. If AI answers are part of your plan, publish an llms.txt with our free llms.txt generator.
Frequently asked
How do you calculate SEO ROI?
SEO ROI = (gross profit from organic customers - SEO cost) / SEO cost. Get the profit side from search volume x click-through rate (visits), then visits x visitor-to-lead rate x lead-to-customer rate (customers), then customers x deal value x gross margin. Use the same time period for profit and cost, and count the months it takes for rankings to arrive, or the result will look better than it is.
What is a good ROI for SEO?
There is no fair single benchmark, because published SEO ROI figures come mostly from agencies measuring their own clients. A useful test is your own: SEO should pay back its cost within the time you are willing to wait (often 12 to 24 months for B2B) and then cost less per customer than your paid channels. Compare the cost per customer in the calculator with the figure from our CAC calculator.
How long does SEO take to pay off?
Usually longer than a paid campaign. Omnius, a SaaS SEO agency, says its projects show early results in 30 to 60 days, meaningful results in 4 to 8 months and significant results in months 9 to 12. The calculator's ramp field spreads traffic growth over the months you choose, so you can see the payback month move as you change it.
What click-through rate should I use for SEO forecasts?
Use your own Search Console data where you have it. Otherwise use a published curve and be conservative. First Page Sage's 2026 table puts position 1 at 39.8%, position 3 at 10.2% and position 10 at 1.6%. GrowthSRC Media measured position 1 at 19% in 2025, down from 28% a year earlier. Ahrefs found that an AI Overview goes with a 58% lower click-through rate for the top result.
Do AI Overviews reduce SEO ROI?
They reduce clicks on the keywords where they appear. Ahrefs compared 300,000 keywords in December 2023 and December 2025 and found that the top-ranking page had a 58% lower average click-through rate when an AI Overview was present. The calculator lets you set the share of your search volume that shows an AI Overview and lowers the click-through rate on that share.
Should SEO ROI use first-year revenue or lifetime value?
Start with first-year gross profit. It is the number you can defend to a CFO, and it keeps SEO comparable with paid channels judged on payback. If your customers stay for several years, raise the years-retained field to see the lifetime view, and say which one you are showing.
