Time and date calculators

Date and age calculations

Date and time calculations come up constantly — in personal planning, employment law and business operations alike. The age calculator computes exactly how many years, months and days have passed since a birth date, correctly accounting for leap years so the result is always precise. The days-between-dates calculator returns the difference between any two dates in days, weeks and months. It is useful for verifying contract deadlines, warranty periods, notice periods and payment due dates. The Polish working-days calculator removes weekends and all statutory public holidays from the total — including New Year, Easter Monday, Labour Day, Constitution Day, Assumption, All Saints, Independence Day and the two Christmas days. This lets employers and employees determine exact delivery or notice-period end dates. Annual leave entitlement in Poland is set by the Labour Code: employees with fewer than 10 years of total work experience receive 20 days per year; those with 10 or more years receive 26 days. The leave calculator applies this rule and shows remaining days for any given start date. The ISO week number (ISO 8601) is the standard used in project management, logistics and ERP systems. Week 1 is defined as the week containing the first Thursday of the year. The week-number calculator displays the week number for any date and shows the corresponding Monday-to-Sunday date range. All our date calculators are free to use, require no registration and are kept up to date with the current Polish public holiday schedule.