Regex Tester & Validator

Matches a date in M/D/YYYY format (leading zeros optional on month and day) where the month is 1-12, day is 1-31, and year is 1900-2099, or alternatively the placeholder text 'N/A' in any letter casing. The gm flags allow validating multiple lines of input at once. Note it does not validate month-specific day counts (e.g., 2/31 would pass), making it suitable for form validation where a date field may be optional.