Date Calculator

This calculator works out the difference between two dates or finds a new date by adding or subtracting days, useful whenever you need an exact figure rather than counting on a calendar. It has two modes, switched using the tabs above the results. In the first mode you enter a start date and an end date, plus whether the end date should be included in the count, and it instantly returns the calendar days between them, the working days (Monday to Friday), the weekend days, the number of complete weeks, an approximate number of months, an exact duration broken into years, months and days, and the day of the week for both the start and end date. In the second mode you enter a starting date, choose to add or subtract, set a number of days, and choose whether to count weekends or working days only, and the calculator returns the resulting date, its day of the week, and the calendar and working days between the two dates. This suits notice periods such as the 42 or 90 days under the Residential Tenancies Act, employment notice and final pay dates, loan terms, or IRD filing deadlines. Note that working days here means Monday to Friday only; it does not currently exclude New Zealand public holidays, so check the exact wording of any legal deadline, as "days", "working days" and "business days" can each mean something different.

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Common date calculations in New Zealand

Date calculators are useful for a wide range of everyday situations. Landlords and tenants use them to calculate notice periods under the Residential Tenancies Act (typically 42 or 90 days). Employers use them to calculate notice periods and final pay dates. Borrowers use them to calculate loan terms and interest periods. IRD uses specific date rules for provisional tax due dates and filing deadlines.

Working days in New Zealand

Working days in New Zealand are Monday to Friday, excluding public holidays. This calculator counts Monday to Friday as working days but does not currently exclude New Zealand public holidays. When calculating legal deadlines such as notice periods, statutory timeframes, or court filing dates, check whether the relevant legislation specifies "days", "working days", or "business days", as each can give a different result. The Employment Relations Act, Residential Tenancies Act, and Contract and Commercial Law Act each have their own definitions.