Validation Rules

Ensure data quality with custom validation rules.

Validation rules ensure that submitted data meets your requirements. Beyond built-in field validation, you can create custom rules with conditions and custom error messages.

Built-in Validation

Each field type has automatic validation:

Custom Validation Rules

Add custom validation to any field:

1. Select the field in the builder
2. Go to the Validation tab
3. Click Add Rule
4. Configure the rule
5. Save

Rule Structure

Each validation rule has:

• Condition: When to show an error
• Message: Error message to display

The rule triggers when the condition evaluates to true for an error state.

Creating Validation Rules

Simple Value Check

Validate the current field’s value:

Rule: length_lt → 10
Message: "Must be at least 10 characters"

Cross-Field Validation

Validate based on other fields:

Rule: "confirm_email" neq "email"
Message: "Email addresses must match"

Conditional Validation

Only validate when certain conditions are met:

IF "country" = "United States"
THEN validate "zip" matches pattern "^\d{5}(-\d{4})?$"
Message: "Please enter a valid US ZIP code"

Validation Operators

All conditional logic operators work for validation:

Text Validation

Numeric Validation

Length Validation

Format Validation

Error Messages

Writing Good Error Messages

• Be specific about what’s wrong
• Tell users how to fix it
• Avoid technical jargon
• Keep it brief

Good:

“Phone number must include area code (e.g., 555-123-4567)”

Bad:

“Invalid format”

Dynamic Error Messages

Include field values in messages using templates:

Message: "Value must be greater than {{ min_value }}"

When Validation Runs

Client-Side (Form Widget)

• On field blur (when user leaves field)
• On form submission attempt
• Immediate feedback to users

Server-Side (Always)

• When entry is created or updated
• When workflows modify values
• When entries are imported

Validation States

Entry Status

Field Status

Each field shows:

• Error message if invalid
• Success indicator if valid (optional)
• No indicator if untouched

Common Validation Patterns

Password Requirements

Rule 1: length_lt → 8
Message: "Password must be at least 8 characters"

Rule 2: not matches_pattern → "[A-Z]"
Message: "Password must include an uppercase letter"

Rule 3: not matches_pattern → "[0-9]"
Message: "Password must include a number"

Phone Number Format

Rule: not matches_pattern → "^\+?[\d\s-()]{10,}$"
Message: "Please enter a valid phone number"

Date Range

Rule: "end_date" lt "start_date"
Message: "End date must be after start date"

Unique Selection

For multiple selects or repeaters:

Rule: Check for duplicates
Message: "Each item must be unique"

Validation in Workflows

Workflows can also validate data:

On Submission

Trigger workflow on form submission to:

• Run complex validation logic
• Check against external data
• Validate across multiple forms

Validation Step

Add a condition step that:

• Checks validation rules
• Updates entry status
• Sends notifications for invalid data

Best Practices

Layer Your Validation

1. Field-level for basic format
2. Custom rules for business logic
3. Workflow for complex validation

Be User-Friendly

• Validate early and often
• Show all errors at once
• Allow submission to save drafts

Test Edge Cases

• Empty values
• Boundary values (min/max)
• Special characters
• Very long inputs

Performance

• Avoid expensive regex patterns
• Limit cross-field validations
• Consider async validation for heavy checks