Regex Tester & Validator

This regular expression matches dates formatted as YYYY-MM-DD specifically for the years 2016 through 2019. It allows for optional leading zeros in the month and day components, successfully matching variations like 2019-1-1 or 2016-12-31. Note that while it restricts days to a maximum of 31, it does not validate the exact number of days in specific months, such as February. It is highly useful for filtering or validating date strings within that exact four-year timeframe.