Validating Dates in DD/MM/YYYY Format Using JavaScript Regular Expression

Validating dates is a common task in programming, and the ability to ensure a date is in a specific format is crucial. In JavaScript, regular expressions provide a powerful tool for performing such validations.

Consider the regex pattern for validating dates in YYYY-MM-DD format:

/^\d{4}[\/\-](0?[1-9]|1[012])[\/\-](0?[1-9]|[12][0-9]|3[01])$/

To adapt this pattern for DD/MM/YYYY, we simply need to flip the group positions for day and year:

^(0?[1-9]|[12][0-9]|3[01])[\/\-](0?[1-9]|1[012])[\/\-]\d{4}$

This updated pattern will validate dates in DD/MM/YYYY format. Additionally, it includes the following considerations:

• Accepts either "/" or "-" as a separator
• Allows days from 1 to 31
• Allows months from 1 to 12
• Validates years from 1900 onwards

To use this pattern in JavaScript, you can assign it to a variable and utilize the test() method to validate a date string:

const dateRegEx = /^(0?[1-9]|[12][0-9]|3[01])[\/\-](0?[1-9]|1[012])[\/\-]\d{4}$/;

const dateString = '12/03/2022';

console.log(dateRegEx.test(dateString)); // Output: true

By leveraging this regular expression, you can ensure the validity of dates in DD/MM/YYYY format, ensuring the accuracy and reliability of your data processing algorithms.