Validation rules supported by internal.js

Validation Rules Cheat Sheet

Add these strings to the rules array inside an element’s data-validate JSON to activate the corresponding behaviour. Multiple rules can be combined; they are applied in order.

Rule	Purpose	Example
noSpaces	Strip all whitespace characters.	["noSpaces"]
digits	Allow only numbers. If noDecimals is not present, a single . is allowed.	["digits"]
fixedDigits:n	Force exactly n digits (non-numeric characters removed). Marks valid only when the length is reached.	["fixedDigits:10"] for a 10-digit phone
range:min-max	Value must be within numeric range (inclusive).	["range:1-100"]
positive	Remove - sign to keep value positive.	["positive"]
noDecimals	Remove any decimal points. Often paired with digits.	["digits","noDecimals"]
fixedDecimals:n	Clamp decimal portion to n places; marks valid when exactly n decimals are present.	["digits","fixedDecimals:2"] for currency
upperCase / lowerCase	Force casing on the entire value.	["upperCase"]
nonZero	Clears the value if it equals "0".	["nonZero"]
noLeadingZeros	Removes extra zeros at the start (e.g., 0012 → 12).	["noLeadingZeros"]
minLength:n	Valid only when the trimmed value has at least n characters.	["minLength:3"]
maxLength:n	Truncate value to n characters.	["maxLength:25"]
exactLength:n	Valid only when the value is exactly n characters.	["exactLength:6"]
email	Basic email pattern validation.	["email"]
url	Basic HTTP/HTTPS URL check.	["url"]
phone	Allows optional + followed by digits.	["phone"]
date	Requires YYYY-MM-DD.	["date"]
dateRange:YYYY-MM-DD-YYYY-MM-DD	Ensures the date falls within the provided range.	["date","dateRange:2024-01-01-2024-12-31"]
futureDate / pastDate	Date must be after/before today. (Use with date.)	["date","futureDate"]
time	Accepts HH:MM in 24-hour format.	["time"]

Example JSON

<input
  id="input_pan"
  data-validate='{
         "rule_name":"kycBlock",
         "rules":["upperCase","exactLength:10","noSpaces"],
         "required":true,
         "show_error":true,
         "error_header":"Invalid PAN",
         "error_text":"PAN must be 10 characters (letters/numbers only)",
         "valid":false
       }'
/>

Tips

• Rules run in the order listed; place sanitising rules (noSpaces, digits) before validators (minLength, range) so the checks see cleaned values.
• You can mix rule types—for example, ["digits","fixedDigits:6","range:100000-999999"] ensures a six-digit OTP within a numeric window.
• Dropdowns typically use validation for presence (required) rather than format, but you can still share rule_name with inputs so buttons enable as a group.