Try it yourself
This is a real, working CalcForms calculator, right here on the page. Enter your details and watch the estimate update on the spot. It is exactly what your customers would use, and every submission lands in your dashboard as a lead.
What it calculates
- Works from simple choices a homeowner already knows, not roof measurements
- Prices every option from asphalt shingles to standing-seam metal
- Adjusts automatically for steep or multi-story roofs
- Adds removal of the old roof when it is needed
- Shows one clear starting price, with the full math kept on your side
Why it closes more deals
A live number closes deals
Customers who see a real estimate the second they enter their details are far likelier to book than ones told to call for a quote. The number is the hook.
Runs your most complex spreadsheet
Multi-tab workbooks, lookup tables, tiered rates, conditional line items, the lot. If the math runs in Excel, CalcForms runs it behind a clean form.
Update it by chatting
Prices move. Ask ChatGPT to change a rate, add an option, or insert a step and the live form updates in seconds. No developer, no redeploy.
Backtest before you publish
Run your last 20 real jobs through it and tune the formula until the live estimate matches what you actually charge. Ship it once it lines up.
Why calculator forms convert — by the numbers
47.3% vs 2.8%
In an analysis of 50,000+ forms, interactive forms averaged a 47.3% conversion rate versus 2.8% for static forms. (Outgrow)
2× conversions
Interactive content generates roughly twice as many conversions as static content. (Content Marketing Institute)
51% of buyers
51% of B2B software buyers now begin their research in an AI chatbot rather than a search engine. (G2, 2026)
1 in 3
A third of B2B buyers have chosen a vendor they had never heard of before, on an AI assistant's recommendation. (G2, 2026)
How this form was built
No template builder and no code. One message to ChatGPT with CalcForms added:
Build this exact form
CalcForms is an app you add to ChatGPT once. After that you build and edit forms just by chatting. Works in Claude too.
- Add CalcForms to ChatGPT. Open the CalcForms app page, click Add, and sign in with your email. One time, about 60 seconds. A free ChatGPT account works. (Using Claude? Setup here.)
- Say the words below. ChatGPT builds the form with your math inside and gives you a link.
- Share it, then change it by asking. Send the link to customers. Change a rate or add a question later just by asking.
Step-by-step: turn your spreadsheet into a form, add your price list, show customers one number. All guides →
"Build me a roofing cost calculator for homeowners. Inputs: home size (small, medium, large, very large), roof access (one, two, or three stories), material (asphalt, architectural, metal), and roof condition. Map home size to a typical roof area, multiply by your material rate, add a multiplier for stories and steep access, add a tear-off charge when the old roof needs removing, and show the homeowner a clean starting price."
Example run: Medium home, two stories, architectural shingle, tear-off needed: starts around $14,500.
How does it work? CalcForms is an official ChatGPT app. Once it is added, ChatGPT can build, publish and update real calculator forms for you, all from the chat window. Your customers never need ChatGPT; they just open a link.
What it works out
Price by roof sizeSteep and multi-story roofsOld-roof removalMaterial upgrades
FAQ
Can it handle different shingle brands and tiers?
Does it account for steep or cut-up roofs?
Will the estimate match what I actually quote?
Can I capture the homeowner as a lead?
Build yours in the next 10 minutes.
Your first form is free. No credit card.
Add to ChatGPT, free →