Date and Time Calculators
Add to Date Calculator: Days, Weeks, Months, Years
Add or subtract days, weeks, months and years from a date. The result with the day of the week, a solution and a calendar.
Day of the Week Calculator: What Day Was or Will Be a Date
Find the day of the week for any date from year 1 to 9999. Solution by Zeller's congruence, day of the year, week number and month calendar.
Time Calculator: Add and Subtract Hours, Minutes, Seconds
Add and subtract hours, minutes and seconds, add a duration to a clock time and find the time between two clock times across midnight.
Business Days Calculator: Working Days Between Dates
Count business days between dates excluding weekends and optional holidays, working hours, and the date after N business days.
Days Calculator: Days Between Two Dates
This free date calculator calculates the difference between two dates. It can also add or subtract from a date. Both calculators work with business days and calendar days.
Age Calculator: Years, Months and Days
Exact age from a date of birth: full years, months and days, total days and weeks, and time until the next birthday.
Work Hours Calculator: Time Card and Pay
Hours worked for a day or week minus breaks, including night shifts, and pay at an hourly rate.
Countdown Calculator: Days Left Until a Date
How many days, hours, minutes and seconds are left until a date: a live countdown to New Year, a birthday or any event.
Recurring Payment Schedule Calculator
Payment dates at a given interval and the running total.
Time Converter: Seconds, Minutes, Hours, Days
Time converter: seconds, minutes, hours, days, weeks, months, years and milliseconds, with a solution and a split into h, min, s.
Julian to Gregorian Converter: Old and New Style Dates
Convert dates between the Julian and Gregorian calendars: Old Style and New Style with a solution and the day of the week.
Unix Timestamp Converter: Timestamp to Date and Back
Converts a Unix timestamp to date and time (UTC and Moscow) and a date to a timestamp. Seconds and milliseconds.
Date and time calculators help you count deadlines and plan: how many days are between dates, what date comes in a month or after 10 business days, which weekday a holiday falls on and how long is left until an event. Every calculation comes with a step-by-step solution.
- Days calculator — the number of days between dates.
- Add to date — years, months, weeks and days forward or back.
- Time calculator — hours, minutes and seconds, across midnight.
- Day of the week — by Zeller's formula, with a month calendar.
- Business days — working days, hours and deadlines.
- Countdown — a live timer to any date.
- Age — Exact age from a date of birth: full years, months and days, total days and weeks, and time until the next birthday.
- Work Hours — Hours worked for a day or week minus breaks, including night shifts, and pay at an hourly rate.