# Build a rule

> The visual rule editor — drag conditions, combine with AND/OR, group with parentheses.

Source: CBX documentation, version 3.x (released). Canonical page: https://docs.configbox.at/docs/admin-guide/rules/build-a-rule. Last updated 2026-07-20.

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> **Audience:** store admins · **Scope:** the rule editor · **Last reviewed:** 2026-07-20

**What this does** — Makes a question or answer conditional: it shows (or hides) only when the
conditions you build here are met. Customers then only ever see valid, relevant choices.

## Before you start

- Decide the sentence you want, in words: *"Show the **Engraving text** question if the answer in
  **Add engraving** is **Yes**."* If you can say it, you can build it.
- The questions/answers the rule refers to must already exist.

## Steps

1. Open the question or answer, expand its **Rule** section, and click **Change**. The rule
   editor opens:

   ![The rule editor](./img/rule-editor.jpeg)

2. At the top, pick the rule's meaning: **Show the question if these conditions are met** or
   **Hide the question if these conditions are met** — whichever reads more naturally.
3. Build conditions from the **Condition Types** tabs:
   - **Answers to questions** — pick a question in the dropdown to see its draggable conditions
     (for a choice question: one per answer; for value questions: its entered value, and its
     price). Drag one into the rule area at the top.
   - **Results of calculations** — drag in a calculation's result to compare against a number.
   - **Customer** — conditions on the customer's group.
4. Set each condition's **operator** by clicking it: *is*, *is not*, *is below*, *is or below*,
   *is above*, *is or above* — and type the value to compare against where the condition takes
   one.
5. Combine multiple conditions by dragging in the **AND** / **OR** combinators (top right). To
   control precedence, select conditions and click **Put in parentheses** — e.g.
   `(Use is Indoor OR Use is Covered) AND Material is Steel`.
6. Housekeeping: **Remove selected** deletes marked pieces; **Limit condition width** compacts
   long chips for readability.
7. **Save** in the editor, then save the question/answer form.

## What happens next

The rule evaluates live on every selection change. When it stops applying, the question/answer
hides or greys out — and what happens to an already-made selection is governed by the
[companion behaviors](https://docs.configbox.at/docs/admin-guide/rules/control-what-happens-on-change).

## Good to know

- **Copy/paste**: the Rule section's buttons copy a whole rule between questions/answers — build
  once, reuse, adjust. **Delete** reverts to "always show".
- Rules on **answers** are how you thin out a choice list per context; rules on **questions**
  remove whole inputs.
- **Copying a product** re-points all rule references to the copy automatically — rules don't
  leak across products.
- Rules re-evaluate on every change across the product; hundreds of deep rules can slow the
  configurator — keep conditions focused.
- A rule only decides *visibility*. Requiring an answer stays with the question's "has to be
  answered" switch; prices stay with pricing.