Conditional logic

1. 1Open the Logic panel in the builder.
2. 2Choose a trigger question — the one whose answer is watched.
3. 3Choose the condition: equals, does not equal, contains, is answered, is greater than, and so on. Which operators are offered depends on the trigger's type.
4. 4Choose the target question and whether to show or hide it.

Rules evaluate live as the respondent types. A hidden question disappears immediately rather than at the page boundary, so the form never briefly asks something irrelevant.

• The question is not rendered, and its answer is not collected.
• If it was marked required, that is not enforced. Nobody can be blocked by a field they were never shown.
• An answer given before the question was hidden is discarded on submit, so a stale answer cannot survive a change of mind.
• The same evaluation runs on the server when the response is submitted. Logic is not something the browser can be talked out of.

A trigger must come before its target. A rule that reads a question further down the form can never fire, because the respondent has not reached it yet — the builder will let you create one but it will do nothing on the live form. If you reorder questions and a rule stops making sense, this is usually why.

Use logicwhen the answer is “should this question be on screen?” It is quicker to author and easier for someone else to read later.

Use ruleswhen you need a value computed, a question required only in some circumstances, or a check that spans several answers — “the end date must be after the start date”. Rules can also hide questions, so a form that already has a rule set is often clearer keeping all its conditions in one place.