Guide · 7 min read

The complete guide to conditional logic in forms

When to branch, how to keep logic readable, and the patterns that lift completion.

Why logic matters

A form that asks everyone everything converts badly. Conditional logic shows each respondent only the questions relevant to them.

The win is twofold: shorter forms complete more often, and the data you collect is cleaner because irrelevant fields are never shown.

Patterns that work

Qualify first: ask a routing question early and branch the rest of the form from it.

Collapse, don't bury: hide whole sections rather than scattering single conditional fields — it's easier to reason about.

Keep it observable: if you can't describe a rule in one sentence, simplify it.

Common mistakes

Referencing a later answer in an earlier rule. Logic should only depend on questions already answered.

Over-branching into many near-identical paths. Prefer one path with a few conditional fields.

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