A date calculator is a tool that helps users determine the difference between two dates or calculate a future or past date based on a specific number of days, months, or years. It can be useful for planning events, tracking deadlines, or simply understanding time intervals. These calculators can be found online or as applications on smartphones. Users typically input the starting date and the desired time frame, and the calculator provides the resulting date or the total number of days between the two dates. This makes it a practical resource for both personal and professional use.