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 reaches you as a lead.
What your customer answers
The live form above asks for these, in this order.
- Their email, so the lead reaches you
- Average monthly electric bill: a number
- Roof exposure: Full sun, Partial, Limited
What they see: Your estimated 25-year savings, worked out from their answers on the spot.
What it calculates
- Savings sized from the monthly bill and roof exposure
- Estimated 25-year savings shown to the homeowner
- Your installed cost deducted before the number is shown, never below zero
- Full sun, partial and limited roofs each get their own production factor
- Sends you the homeowner's lead with their bill and projected savings
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 are worth it, 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)
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 Install plugin, 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 a solar savings calculator. Inputs: average monthly electric bill and roof exposure (full sun 1.0x, partial 0.85x, limited 0.65x production). Take the bill times 12 months times 25 years, apply the exposure multiplier, subtract my $14,000 installed cost, never show less than zero, and round to whole dollars. Show the homeowner one number: their estimated 25-year savings. Do not show my installed cost figure."
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
Savings from your billRoof exposure factorInstall cost deducted25-year total
Last updated 6 October 2026
FAQ
Can it apply rebates and local incentives?
Can it show a loan option, not just cash?
Does the homeowner see my installed cost?
Can I validate it against deals I have closed?
Build yours in the next 10 minutes.
Free in ChatGPT, unlimited forms and submissions. No credit card.
Add to ChatGPT, free →