Build a calculation

Version

3.x

Updated

2 Aug 2026

View markdown

Audience: store admins · Scope: creating a calculation and attaching it · Last reviewed: 2026-07-20

What this does — Creates a named formula that turns the customer's current selections into a number, and wires it into a price (or weight, or an input bound). Example built below: an area price — entry in Width × entry in Height × 0.20.

Before you start

• Read where prices come from so the calculation lands in the right place.
• The questions the formula reads must exist.

Steps

1. Go to Calculations, click Add, name the calculation (you'll pick it by this name later), choose the product it belongs to and the style Formula.

2. Build the expression in the editor:

   

   • Drag Calculation Terms into the Calculation area: the arithmetic chips (+ − * /), a Number chip (type its value, e.g. 0.20), and terms from the tabs:
     • Questions — pick a question to drag in its Entry (what the customer entered/selected), its price, or its custom fields. Each question term has a small "or …" box — the fallback value used while the question has no entry yet; set it (usually 0 or 1) so the price never shows blank.
     • Calculations — the result of another calculation of this product; this is how you compose small readable pieces instead of one monster formula.
     • Customer — values from the customer's group, for segment-dependent math.
     • Functions — Round, Lowest value, Highest value (and any store-specific extras): each parameter is a slot you drop further terms into.
   • Arrange chips left-to-right; normal arithmetic precedence applies, and Put in parentheses groups selected chips. Remove selected deletes; Limit term width compacts long chips.

3. Save.

4. Attach it — nothing happens until you do:

   • Open the question (or answer) → Calculations section → pick the calculation as its Price Calculation (or Recurring Price / Weight Calculation), or
   • use it as a Calculated Minimum/Maximum Value on a numeric question, or
   • reference it from a rule ("Results of calculations") or from another calculation.

   

5. Check it live: open the configurator, change the inputs, watch the price move.

The special "Regarding Question" term

In the Questions tab, Regarding Question means "whatever question this calculation is attached to". A calculation built with it (e.g. Entry in Regarding Question × 2.5) can be attached to many questions at once and always reads its own question — one formula instead of ten near-copies.

When Formula isn't the right style

• Code — a typed expression, faster for totals-based math ("12% of the running total") and for formulas easier typed than dragged: bind questions to placeholders A–D and write A * B / 1000000 * 65. Keywords give access to totals, question entries/prices and other calculations. → Write a code expression
• Matrix — a lookup table when pricing is a table: choose what keys the rows and columns (a question's value or a calculation's result), fill the grid (or import an Excel file), and pick the matching mode — exact value, or round up/down to the next bracket. Multipliers can scale the looked-up cell by a quantity question or another calculation. → Price with a matrix

All three styles attach identically (step 4) and can reference each other.

Good to know

• Compose, don't inflate: several small named calculations referencing each other stay debuggable; one giant formula doesn't.
• Calculations recompute on every selection change — very deep chains can slow the configurator.
• The calculation edit form lists where it is in use — check before changing shared pieces.
• Copying a product copies its calculations and re-points every reference automatically.
• Author in the base currency; never bake tax or currency conversion into a formula.