Website ROI calculator
Visitors, conversion rate, lead value and build cost, as payback time.
FreeRuns in your browserNo signupUpdated 2026-10-29
Payback
4.3 mo
Months of extra revenue to cover the build
Extra revenue per month
$2,250
$5,625 today → $7,875 after uplift
| Today | After | |
|---|---|---|
| Leads per month | 37.5 | 52.5 |
| Customers per month | 9.4 | 13.1 |
| Revenue per month | $5,625 | $7,875 |
| Net gain after running cost | – | $2,100 |
| First-year net and ROI | – | $16,200 150% |
The uplift is the assumption that matters. Redesigns that fix slow pages, unclear offers or weak calls to action commonly lift conversion by 20 to 100%; a visual refresh alone often lifts it very little.
About this tool
How it works and how to read the result.
Need this done for you?
Website design & development
Company websites designed and built to win trust and enquiries.
See the serviceWhat it does
A website ROI calculator connects a build cost to the thing it is supposed to improve: enquiries that become customers. Enter monthly visitors, the share who convert today, the share of leads you close and what a customer is worth. Set the uplift you expect from the new site, plus the build and running costs. The page shows leads, customers and revenue before and after, the net monthly gain, how many months it takes to pay back the build, and the first-year return. It runs in your browser.
How to use it
- Enter monthly visitors and today's conversion rate from your analytics.
- Set the share of leads that become customers and the value of one customer.
- Choose the conversion uplift you expect from the new site. Be conservative, and test a low and a high value.
- Enter the build cost and the monthly running cost.
- Read payback and first-year ROI, then copy the summary.
How to read the result
Take a site with 2,500 visitors a month converting at 1.5%, so about 38 leads. Closing 25% gives around 9 customers worth $600 each, or $5,625 a month. A new site that lifts conversion by 40% produces about 53 leads, 13 customers and $7,875, an extra $2,250 a month. After $150 of running cost, the net gain is $2,100, so a $9,000 build pays back in about 4.3 months. First-year net is $16,200, a return of about 150% on the $10,800 spent.
Halve the uplift to 20% and the extra revenue is $1,125, net $975, and payback stretches to just over 9 months. Still positive, but the margin for error is thinner.
If payback shows a dash, the extra revenue does not cover the running cost at that uplift. Either the traffic is too low for conversion changes to matter, in which case the budget belongs in traffic first, or the customer value is too small.
Our website design and development projects start by agreeing which of these numbers the new site is meant to move. Estimate the build cost with the website cost calculator.
Questions
Frequently asked.
What uplift should I assume from a new website?
It depends on what is wrong today. Fixing a slow site, an unclear offer or a buried contact form commonly lifts conversion by 20 to 100%. A visual refresh of a site that already works well may lift it by very little. If you have no data, run the numbers at 20% and 50% and see whether both pay back.
Where do I find my current conversion rate?
In your analytics, divide form submissions, calls or purchases by sessions for the same period. GA4 reports key events per session if you have marked your conversions as key events. If you have not, count enquiries by hand for a month and divide by sessions.
What counts as the value of a customer?
For a one-off purchase, the average order margin. For services or subscriptions, the revenue a typical customer brings in the first year. Use margin rather than revenue if you want a stricter test. Keep the same definition when you compare projects.
More in Business & pricing
Related tools.
Your next move
Like what you see? Tell us about it.
A process that takes too long, a website that undersells you, or an idea ready to take shape. Tell us where you are and we will suggest a useful next step.
India · Working with clients worldwide