Date Calculators — Date

Add or subtract days, weeks, months, or years from any date to find the resulting date.

Convert between Gregorian calendar dates and the Chinese lunar calendar.

Find the date of Chinese New Year for any year based on the lunar calendar.

Calculate the exact number of days, weeks, months, and years between any two dates.

Calculate date of birth from current age or age at a specific date.

Generate a list of all dates between two dates with customizable intervals.

Convert any date to its ordinal day number within the year (1-366).

Convert between calendar dates and Julian Day Numbers used in astronomy and programming.

Find the day number (1-366) of any date within its year.

Find when DST begins and ends for any year and location with clock change reminders.

Find how many days are in any month of any year including February in leap years.

Count how many days have passed since any historical date or personal milestone.

Count the exact days remaining until any future date — holidays, deadlines, or events.

Find what decade, century, and millennium any year belongs to.

Calculate pregnancy due date from exact conception date instead of last menstrual period.

Find the date of Easter Sunday for any year using the computus algorithm.

Find the date of US Election Day for any year using the first Tuesday after the first Monday rule.

Calculate your exact age in years, months, days, hours, minutes, and seconds from birth date.

Find all Friday the 13th dates in any year or range of years.

Find the dates of all full moons in any year with moon phase names.

Convert between Gregorian and Hebrew calendar dates with Jewish holiday awareness.

Find how many days remain until the next Friday or any specific weekday.

Find the ISO 8601 week number for any date and the start/end dates of any week.

Check if any year is a leap year and list all leap years in a given range.

Calculate the number of complete months between two dates.

Convert between Gregorian, Hijri, and the Persian Solar Hijri (Jalali) calendar.

Find which fiscal or calendar quarter any date falls in and the quarter start/end dates.

Find the estimated start date of Ramadan for any year based on the Islamic lunar calendar.

Calculate exactly how long you have been in a relationship in years, months, and days.

Find the exact dates of solstices and equinoxes for any year and hemisphere.

Calculate days, months, and years of sobriety from your clean date.

Find the date of Thanksgiving for any year in US and Canadian calendars.

Calculate the number of weeks between two dates or weeks from now to a date.

Find what day of the week any date falls on — past, present, or future.

Calculate years, months, and days since your work start date for anniversary milestones.

Calculate the decimal fraction of a year between two dates for financial calculations.

Find the exact date ranges for all 12 zodiac signs including cusps.

Predict when your baby will arrive

Plan topic clusters and publishing schedules for topical authority

Find what day of week a date falls on

Calculate pregnancy due date

Calculate accumulated heat units (GDD) for crop development and pest management

Plan annual promotional calendar, forecast campaign uplift and ROI to maximize revenue without over-promotion

Calculate QALYs and cost-effectiveness for health interventions