Logic
Logic on every question type
Show or hide questions, route people between pages and endings, pipe answers into later text and calculate values.
Rules on any question
Every question has a Show only if… rule. The condition can look at another answer, a hidden field from the link, or a calculated value, and it can compare with equals, contains, greater than, is empty, is any of, and more. Combine several conditions with and or or.
Routing between pages
Each page can have routes: if these conditions match, go to that page, that ending, an external URL, or disqualify the response. The first matching route wins; otherwise people continue to the next page. Routes only point forward, so a form can never loop.
Path map
The logic tab draws every page and ending with the routes between them, so you can check a branching form without clicking through it.
Calculations and piping
Calculated fields do arithmetic on answers and can feed other rules. Refer to a question as {q_id} in text and its answer is inserted for the respondent.
Checked twice
The browser uses the rules to hide and show questions as people type. The server applies the same rules again when the response arrives, and a hidden question stores no answer.