SERVICE 05 / 09
PDF Forms with Auto-Calculations
Stop checking other people's maths. Line totals, tax, discounts, dates and scores calculate themselves while the form is being filled — and can't be typed over.
Try it
Change a number. Watch the rest follow.
This is how a calculating order form behaves. In your PDF, the same logic runs inside the free Acrobat Reader.
amount = qty × rate
discount = subtotal × discount %
tax = (subtotal − discount) × 8%
total = subtotal − discount + tax
What we can calculate
If it's a rule, it can be a formula.
Totals and line items
Quantity × price, column sums, averages, minimums and maximums.
Tax, discounts and fees
Percentages, tiered discounts, shipping rules and rounding.
Dates
Age from date of birth, days between dates, due dates and expiry dates.
Scores and ratings
Assessment and survey scoring, with bands such as low / medium / high.
Conditional logic
Show, hide or require fields depending on earlier answers.
Protected results
Calculated fields are read-only, so totals can't be overwritten by hand.
How we build the maths
01
Write down the rules
In plain words: “10% off orders over $500”, “tax applies after discount”.
02
Formula sheet
We turn them into formulas and confirm them with you before building.
03
Build and order
Calculations set up and run in the right order, so totals never lag behind.
04
Test with real numbers
Including edge cases: zero, blanks, decimals and very large values.
Forms that usually calculate
Order forms
Invoices & quotes
Expense reports
Timesheets
Budgets
Assessments & scorecards
Mileage logs
Questions about calculations
Do calculations work in every PDF viewer?+
They work in Adobe Acrobat Reader on desktop and mobile. Some browser and phone viewers ignore form scripts, so totals may not update there. We test the viewers you name and can add a short “open in Acrobat Reader” note on the form.
Can I change the rates later?+
Yes. We can keep rates in editable fields, or update the formulas for you when prices change.
Can you calculate in my local currency and date format?+
Yes — currency symbols, decimal separators and date formats are set to match your region.
Would a spreadsheet be better?+
If people need to send a fixed, signable document, a calculating PDF wins. If it's an internal working file, a spreadsheet may be simpler — we'll say so honestly.