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Forms

Conditional logic

Logic makes one form work for different people: skip the questions that don't apply, and route each respondent to the pages that do. There are two kinds, and both are built visually in the form editor.

Show a field conditionally

Any field can carry a visibility condition: show this field only when an earlier field's answer matches. A field with no condition always shows.

Open a question in the page editor and tick Only show this question when… to add one. The condition must point at a field on a previous page — a field can't depend on an answer from its own page or a later one, so the control doesn't appear at all on page 1. A hidden field is simply skipped; nothing is recorded for it.

Branch between pages

Each page can end with fork rules: "if the answer to X is …, then go to page Y." They live under After this page in the page editor, numbered rule 1, rule 2, and so on. When the respondent finishes the page, big checks the rules in that order and the first match decides where they go next. Things to know about targets:

  • A rule can point at any other page — later or earlier — or straight to submit to end the form early. What big rejects is a loop: a route that could send someone round in circles won't save.
  • The destination list also offers + A new page. Picking it creates the page and points the rule at it in one step, which is how you build a branch on page 1 of a new form — there is no other page to choose yet.
  • Everyone else is where a respondent goes when no rule matches. Leave it alone and that's the next page in order, or submit if this is the last page.
  • A rule that's missing its question, its answer or its destination routes nobody. The editor says so under the rule rather than saving a branch that can never match.

A page can hold up to 10 fork rules.

What conditions can test

The comparisons available depend on the field type you're testing:

Field typeAvailable comparisons
Short text, emailequals, doesn't equal, contains
Long textcontains
Instagram handleequals, doesn't equal
Number, ratingequals, doesn't equal, at least, at most
Single choice, dropdown, agreement scaleequals, doesn't equal
Multiple choicenone — can't be tested (yet)

So "rating at most 3 → go to the feedback page, everyone else → submit" works; branching on a multiple-choice answer doesn't. A question big can't test never appears in a rule's question picker, so if one is missing from the list, check its type first.

A worked example

Say you're screening collaborators:

  1. Page 1 asks "Are you a brand or a creator?" (single choice).
  2. A fork rule on page 1: brand → page 2 (budget questions); everyone else → page 3 (portfolio questions).
  3. On page 2, a "Budget" number field with a visibility condition on an earlier answer, shown only when relevant.
  4. Page 2's exit jumps straight to submit, skipping the creator pages.

One form, two experiences, and nobody sees a question that wasn't meant for them.