Validation Rules

Validation ensures respondents provide data in the correct format before submitting. Set rules on individual fields: required, min/max length, patterns, and custom error messages.

Setting validation

Click any field on the canvas
Open the Validation section in the right panel
Add rules

Common validation rules

Required

Toggle Required on to prevent submission without this field. A red asterisk (*) appears next to the field label.

Text validation

Rule	Description	Example
Min length	Minimum characters	Min 2 for names
Max length	Maximum characters	Max 500 for messages
Pattern (regex)	Must match a regular expression	Email format, phone format
Exact match	Must equal a specific value	Confirmation fields

Number validation

Rule	Description
Min value	Number must be at least this value
Max value	Number must not exceed this value
Integer only	No decimal values
Step	Must be a multiple of this value (e.g., step 5: only 5, 10, 15...)

Date validation

Rule	Description
Not in past	Only future dates
Not in future	Only past or present dates
After date	Must be after a specific date
Before date	Must be before a specific date

File upload validation

Rule	Description
Allowed types	Restrict file types (e.g., PDF only, images only)
Max file size	Maximum size per file (e.g., 10MB)
Max files	Maximum number of files

Custom error messages

Each validation rule has a default error message. Override it for a better user experience:

Default	Custom
"This field is required"	"Please enter your email address"
"Value is too short"	"Company name must be at least 2 characters"
"Invalid format"	"Please enter a valid US phone number (e.g., 555-123-4567)"

Set custom messages in the Error message field below each validation rule.

Cross-field validation

Validate fields against each other:

Rule	Configuration
End date after start date	End date: "After" → reference Start date field
Confirm email matches	Confirm email: "Exact match" → reference Email field
Max total quantity	Calculated field that sums quantities, validated to be under a max

Validation timing

When	Behavior
On blur	Validates when the user clicks away from the field. Default behavior.
On submit	Validates only when the submit button is clicked. All errors shown at once.
Real-time	Validates as the user types (for pattern matching). Shows a checkmark when valid.

Configure per-field in Validation → Trigger.

Visual feedback

When validation fails:

The field border turns red
The error message appears below the field in red text
The form cannot be submitted until all errors are resolved
A summary of errors appears at the top of the form (if multiple errors)

When validation passes:

The field border returns to default
A green checkmark appears (if real-time validation is enabled)

Common validation patterns

Field	Rules
Email	Required + pattern (email format)
Phone	Pattern (phone format for target country)
Password	Min 8 chars + pattern (at least 1 uppercase, 1 number)
URL	Pattern (starts with `http://` or `https://`)
Zip code	Pattern (5 digits or ZIP+4 format)
Age	Required + min 18 + max 120

Tip

Write custom error messages that tell the user what to do, not just what went wrong. "Please enter a valid email address (e.g., name@company.com)" is more helpful than "Invalid format."

Note

Validation is client-side for instant feedback, but all rules are also enforced server-side. Users cannot bypass validation by modifying the browser.