Documentation Index
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Conditional logic lets you show or hide fields based on answers to earlier questions. Rules are evaluated in real time — fields appear and disappear as the user fills out the form.
Structure
Each field can have one conditionalLogic rule:
{
"id": "details",
"type": "textarea",
"label": "Tell us more",
"conditionalLogic": {
"action": "show",
"match": "all",
"conditions": [
{
"fieldId": "satisfied",
"operator": "equals",
"value": "no"
}
]
}
}
Properties
| Property | Type | Description |
|---|
action | "show" | "hide" | Whether to show or hide the field when conditions are met |
match | "all" | "any" | all = AND logic (every condition must pass), any = OR logic |
conditions | Condition[] | One or more conditions to evaluate |
Condition Structure
{
"fieldId": "plan_type",
"operator": "equals",
"value": "pro"
}
| Property | Type | Description |
|---|
fieldId | string | The ID of the field whose value is checked |
operator | ConditionOperator | The comparison to perform |
value | string | number | The value to compare against (not required for is_empty / is_not_empty) |
Operators
| Operator | Description | Works With |
|---|
equals | Exact match | All types |
not_equals | Does not match | All types |
contains | Value includes the string | text, textarea, email |
not_contains | Value does not include the string | text, textarea, email |
greater_than | Numeric greater than | number, rating, scale |
less_than | Numeric less than | number, rating, scale |
is_empty | No value entered | All types |
is_not_empty | Any value entered | All types |
Examples
Show a follow-up field
Show a text field only when the user selects “Other” from a radio:
{
"id": "role_other",
"type": "text",
"label": "Please specify your role",
"conditionalLogic": {
"action": "show",
"match": "all",
"conditions": [
{ "fieldId": "role", "operator": "equals", "value": "other" }
]
}
}
Hide a field based on NPS score
Hide a question unless the NPS score is low:
{
"id": "what_went_wrong",
"type": "textarea",
"label": "What could we improve?",
"conditionalLogic": {
"action": "show",
"match": "all",
"conditions": [{ "fieldId": "nps", "operator": "less_than", "value": 7 }]
}
}
Multiple conditions (AND)
Show a field only if the user is a Pro customer AND has submitted before:
{
"conditionalLogic": {
"action": "show",
"match": "all",
"conditions": [
{ "fieldId": "plan", "operator": "equals", "value": "pro" },
{ "fieldId": "returning", "operator": "equals", "value": "yes" }
]
}
}
Multiple conditions (OR)
Show a field if the user selected either “email” or “phone”:
{
"conditionalLogic": {
"action": "show",
"match": "any",
"conditions": [
{ "fieldId": "contact_pref", "operator": "equals", "value": "email" },
{ "fieldId": "contact_pref", "operator": "equals", "value": "phone" }
]
}
}
How It Works
- Conditions reference fields by ID — the
id property on a FormField
- Fields referenced in conditions must appear before the conditional field in the
fields array
- Hidden fields are excluded from submission — their values are not sent
- In conversational mode, hidden fields are skipped automatically in the navigation sequence
- The
statement and divider types are always excluded from submissions regardless of visibility
