Interactive calculators are among the highest-converting lead magnets on the web. Form Forge’s 8 calculator form templates are built around the calculation field and cover the most common calculator use cases. Every template has the formulas pre-configured — drop it in, customize the labels, publish.
Project type dropdown, scope options (checkboxes adding cost), urgency multiplier, live total with currency prefix. For service businesses and agencies displaying estimated pricing on their website.
Loan amount, interest rate, term (years), calculated monthly payment and total interest. Standard amortization formula.
Investment amount, expected return percentage, holding period, calculated future value and gain. For financial services and investment platforms.
Package weight, origin, destination, service level, calculated shipping cost based on your rate table (encoded in conditional calculation fields).
Weight, height, calculated BMI with a result label (“Underweight,” “Normal,” “Overweight,” “Obese”) using conditional logic. For health and fitness sites.
Number of rooms, distance, date, optional extras (packing, storage), calculated total moving cost. For moving companies.
Current savings, monthly contribution, target amount, expected interest rate, calculated months to reach goal. For personal finance sites.
Current monthly electric bill, roof size, sun exposure, calculated estimated savings per year and payback period. For solar installers.
Interactive calculators are the secret weapon of content marketing. They work because:
Marketers report that calculator forms convert at 3–5x the rate of standard lead capture forms because users self-select into qualified leads based on the calculator’s output.
Form Forge’s calculation field supports:
+, -, *, /, %, parentheses)round, min, max, abs, sqrt, if){field_id} syntaxif({plan} == 'premium', {base} * 0.8, {base})Most templates use 2–5 calculation fields layered on top of user input fields. A pricing calculator might have a subtotal field, a discount field, a tax field, and a final total.
Calculator forms update in real time as users type or select options. No “Calculate” button. The answer appears instantly, which makes the interaction feel responsive and polished.
A common pattern: let users see a partial result (the calculated number) but require email to “get the full report” or “see the breakdown.” Form Forge supports this via multi-step:
Typically 50%+ of users who complete step 1 will submit their email in step 2 because they’ve already invested in the experience.
After submission, Form Forge can email the result to the user as a formatted receipt or even generate a PDF version of the results. Useful for:
Get Form Forge — from $49/year →
Calculator templates are included in every version of Form Forge. The calculation field is a paid-plan feature.