Date Calculator

Doing date maths in your head is surprisingly error-prone. Months have different numbers of days, leap years slip in a 29 February, and the moment holidays and weekends enter the picture you are practically guaranteed to miscount. The Date Calculator takes that off your hands and bundles seven calculation types in one tool, so you have the right view for every date question.

The difference mode counts the days, weeks and months between two dates - handy for contract terms, trip durations or the question of how long ago something was. The add-and-subtract mode shifts a date forward or back by a set number of days, weeks, months or years and tells you instantly where you land.

The centrepiece for anyone with official or legal matters is the deadline calculator. It follows the rules of the German Civil Code: Section 187 sets when a deadline starts, Section 188 when it ends, and Section 193 shifts a deadline end that falls on a Saturday, Sunday or public holiday to the next working day. It is exactly this shift that simple calculators get wrong - and it can decide whether a deadline is met or missed. You choose between an event deadline and a start deadline, plus your federal state for statewide holidays. Local exceptions must also be checked for the relevant location.

On top come the everyday calculation types. The age calculator tells you exactly how old someone is to the day, including days lived. The countdown counts down the days to an event, be it a holiday, a birthday or a submission. The weekday calculator reveals what day a date falls on, and the calendar-week view outputs the CW per ISO 8601.

Statewide holiday rules are stored for all 16 federal states, including the movable days around Easter. Because holidays differ by region, the choice of state matters - Corpus Christi, for instance, is a holiday in Bavaria but not in Berlin. Notices flag local exceptions: Assumption Day applies only in certain Bavarian municipalities, the Peace Festival only in Augsburg, and Corpus Christi only in certain municipalities in Saxony and Thuringia. Check these cases for the relevant location.

Everything runs in your browser, no signup and without any date going to a server. You can copy results to reuse them in an email, a calendar or a form. The calculator is a practical aid; for legally important deadlines, verify the result for the individual case.