SEO ROI Calculator
Model the return on an SEO investment: project traffic growth, turn it into conversions and revenue, and see net gain, ROI, and payback month. Updates as you type. Runs in your browser.
How it works
Enter six inputs, current and projected monthly organic visitors, conversion rate, value per conversion, monthly SEO investment, and a time horizon. The calculator ramps traffic linearly from current to projected across the horizon and, each month, converts the incremental visitors (the lift over your starting baseline) into revenue.
It then compares cumulative incremental revenue against cumulative cost to find your payback month, total net gain, and ROI, and shows the monthly revenue ramp as a chart with the break-even month highlighted.
Everything recalculates as you type, entirely in your browser.
How this model differs
Most SEO ROI calculators ramp traffic in a straight line and start counting revenue in month one. That is the flaw worth fixing, because it front-loads return that does not exist and sets a plan up to miss its early numbers.
Growth is modelled on an S-curve, not a line
Organic growth lags, then compounds, then flattens. Nothing ranks in the first weeks, the middle of the period carries most of the movement, and the last months add less than the middle did. A linear model gets the total roughly right and the shape completely wrong, which matters because programmes are cancelled on the shape.
The lag is an input, not an assumption
New pages rarely move inside a quarter. Setting that lag explicitly is what separates a forecast someone can defend in month three from one that looks broken. If your plan cannot survive three months of near-zero, it is worth knowing that before it starts rather than after.
Revenue comes from a funnel, not a flat value
Visitors become leads at one rate, leads become opportunities at another, and opportunities close at a third. Collapsing all of that into a single value per visit hides which assumption the answer actually depends on. Change the close rate here and watch how much more it moves the total than traffic does.
The answer is a range
A single number gets quoted in a board deck and then missed. Three scenarios make the uncertainty explicit, which is both more honest and more persuasive than false precision.
Paid is the comparison that matters
The first question any CFO asks is what the same money does in ads. Paid buys clicks once. Organic buys visits that keep arriving after the spend stops. Both are shown here so the trade is visible rather than argued.