Conditional logic and add-on fields

The Conditional logic switch, Price field, Add-on quantity, and Quantity — four settings that unlock the app’s two most powerful features.

Four settings appear on nearly every option, and each one connects to a larger feature. This page explains what each setting does and where to find it.

Turning on Conditional logic reveals the rule builder directly underneath.

Conditional logic

Turns on rules that show or hide the option based on what the customer has already selected.

Tab	Basic
Default	Off
Available on	All 32 option types, including Section and the visual statics

What happens when you turn it on

A rule builder appears directly underneath, with three parts:

Part	Choices
Action	Show or Hide this option when the conditions are met
Match	all conditions or any condition
Conditions	One or more rows: a source, an operator, and a value

The source of a condition can be another option in the same option set, or the Shopify variant the customer selected. This lets you display an option only for the Large size, for example.

Two things to know first

• The available operators depend on the type of the source option. A text source offers contains and character-count comparisons, a checkbox source offers selection-count comparisons, and a switch source offers only is enabled and is disabled.

• A hidden option is not validated. A required option that is currently hidden by a rule cannot block Add to cart.

Putting the rule on a Section

Section also supports conditional logic. A rule on a section shows or hides everything inside it at once, so if you are applying the same rule to six options, put it on the section that contains them instead.

For full detail, see Conditional logic, the operators reference, and conditions based on Shopify variants.

Price

Adds an extra charge to the option.

Tab	Basic tab, under Add-on Settings
Default	No add-on
Available on	At option level: Text, Textarea, Number, Switch, Color picker. At option value level, in the values table's Price column: all nine selection types with values. Dimension has its own price and formula fields

Where the price is set depends on the option type. An input option has one answer, so it has one price. A selection option has several choices that may cost different amounts, so the price is set on each value. See Where you can set add-ons.

Selecting the field opens a dialog with three tabs, which are three different ways to charge:

Tab	What it does	Stock tracked?
Existing product	Links a product and variant you already sell. The price comes from that variant.	Yes
New product	The app creates a product at the price you type.	Yes
Fixed amount	Adds money to the order with no product behind it.	No

Fixed amount is not supported on Shopify POS. If you sell in person, use one of the product-backed modes. See POS limitations.

Once a value is linked to a product, a Product column appears in the values table, with a link to open that product in Shopify admin.

For full detail, see Add-on pricing.

Add-on quantity

Controls how the add-on charge scales with the main product's quantity.

Tab	Basic, in the Add-on card
Default	Default
Available on	Every type that can carry an add-on

This dropdown applies only when the option has a charge. On an option with no add-on, it has no effect — the app says so in the field's own tooltip.

The dropdown groups the eight modes by who decides the quantity.

Group	Mode	Behavior

Group	Mode	Behavior
Counted automatically	Default	Matches the main product quantity.
	One time charge	Always 1, whatever the main quantity.
Set by you	Fixed quantity	A fixed number you set.
	Dynamic quantity	Quantity you set × main product quantity.
Set by the customer	Fixed quantity (by customer)	Customer enters a quantity; that’s the number of add-ons.
	Dynamic quantity (by customer)	Customer’s quantity × main product quantity.
	Mixed quantity	A quantity box per option value. Multi-select options only.
	Per character	Charged by how many characters the customer typed. Text and Textarea only.

Three of them — One time charge, Fixed quantity, and Fixed quantity (by customer) — are unavailable when the option's price uses Fixed amount, and are greyed out in the dropdown.

Each mode is explained with a worked example in Advanced add-on modes.

Quantity

Sets the number used by two of the modes above.

Tab	Basic, in the Add-on card
Default	Empty
Available on	Appears only when Add-on quantity is Fixed quantity or Dynamic quantity — the two Set by you modes

• With Fixed quantity, this is the exact number of add-ons added, regardless of the main product's quantity.

• With Dynamic quantity, this is multiplied by the main product's quantity.

How the four settings interact

Combination	Result
A priced option hidden by a rule	Not shown, not charged. Hiding an option removes its charge.
A priced option with a Default value	Charged the moment the page loads, before the customer chooses anything.
A multi-select option with prices	Every selected value is charged. Cap it with Max selections.
A required option hidden by a rule	Not enforced while hidden.
A priced option on POS with Fixed amount	Not supported. Use a product-backed mode.