DocumentationDoorFall FormsForms & Builder

Conditional Logic

Show, hide, require or make fields optional using answers from other fields.

What conditional logic does

Conditional logic lets an answer control another field.

Examples:

  • Show an address only when a visitor answers Yes.
  • Show a company field only for Business customers.
  • Make a follow-up question required for a certain answer.

Enable

Select a field and enable Conditional Logic.

Action

Choose:

  • Show this field
  • Hide this field
  • Make this field required
  • Make this field optional

Matching

When using several rules, choose:

  • All rules must match — AND logic
  • Any rule can match — OR logic

Rule field

Select another answer field as the source.

Conditions

Available conditions:

  • Equals
  • Does not equal
  • Contains
  • Does not contain
  • Greater than
  • Less than
  • Is empty
  • Is not empty

Rule value

For choice fields, select one of the defined choices.

For text/number-like fields, enter the comparison value.

Example: conditional address

  1. Add a Yes / No field named Do you need installation?
  2. Add an Address field.
  3. Select Address.
  4. Enable Conditional Logic.
  5. Choose Show this field.
  6. Choose the Yes / No field.
  7. Select Equals.
  8. Select Yes.
  9. Save.

The Address field now appears only when the visitor answers Yes.

Last updated August 19, 2026