Form validation

Collect accurate information from your respondents by validating form inputs. Define validation rules using logic conditions, regular expressions or out-of-the-box validation rules.

Set a validation rule

Click on the question or field you would like to add validation for and open the Validation section by clicking the settings icon. Then, choose a Validation pattern.
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Validate with Regular Expressions

Choose the Regex validation pattern to validate a form input with a regular expression. Regular expressions define a rule for the type of input you want to accept.
 
See here for a list of popular regular expressions. Here are some examples:
Purpose
Regular expression
Whole numbers
^\d+$
Alphanumeric without space
^[a-zA-Z0-9]*$
Alphanumeric with space
^[a-zA-Z0-9 ]*$
URL
https?:\/\/(www\.)?[-a-zA-Z0-9@:%.\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%\+.~#()?&//=]*)
Decimal numbers
^\d*\.\d+$
Whole and decimal numbers
^\d*(\.\d+)?$
 
Copy and paste one of the regular expressions above into the Regex field. Test your form using the Preview mode!
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Validate text length

Use the min and max length validation rules to specify the accepted length of text inputs.
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Validate with logic

Choose the Condition validation pattern to validate a form input based on an arbitrary condition.
 
For example, here we specify that an input must contain either gmail or yahoo.
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The Email input field type validates email addresses out of the box.
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Custom error messages

Provide an Error message through the right-hand side settings to override the default warning message. For example, here we specified Your pin must be exactly 6 characters to be the error message.
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Testing validation logic

Go to Preview mode and click on the Next or Submit button. You’ll see a warning message appear if your inputs don’t match your validation rules.