Free Date & Time Calculators
11 free tools · Calculate ages, date differences, countdowns, and time conversions.
11 free date & time calculators
Browse all 300+ calculators →Age Calculator | Exact Age, Milestones & Birthday Countdown
Calculate your exact age in years, months, days, hours, and minutes. Includes next birthday countdown, zodiac sign, Chinese zodiac, generation, and age milestones.
Date Difference Calculator | Days Between Two Dates
Calculate the exact number of calendar days, business days, weeks, months, and years between any two dates. Includes hours, minutes, seconds, leap year count, and inclusive/exclusive endpoint options.
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates. Supports seconds and milliseconds.
Day of Week Calculator | What Day Was Any Date?
Find the day of the week for any date, past, present, or future. Shows ISO week number, day of year, quarter, leap year status, zodiac sign, and a mini calendar view. Includes famous historical dates and day-offset shortcuts.
Work Hours Calculator | Time & Pay
Calculate total work hours between a start and end time, with optional break deductions.
Shift Schedule Creator | Automatic Shift Planner
Automatically generate weekly shift schedules for any team. Add workers, define shift types, set preferences and days-off constraints, then auto-generate a balanced calendar. Download as PDF or CSV.
Countdown Calculator | Days Until Any Event
Live countdown to any date with days, hours, minutes, seconds, progress bar, business days, and saved countdowns.
Time Duration Calculator
Add or subtract time durations. Convert hours, minutes, and seconds.
Business Days Calculator
Count working days between two dates, add or subtract business days to find deadlines, and run a countdown, with US & UK holiday presets, Mon–Fri/Sun–Thu/Mon–Sat work week options, and detailed breakdowns.
Time Zone Converter | World Clock & Meeting Planner
Convert times between any of 400+ time zones instantly. Compare multiple cities side by side, find the best meeting time across zones, and see DST change dates for every region.
Week Number Calculator | ISO Week & Year Calendar
Find the ISO week number for any date, list all weeks in a year, and calculate the date range for any given week. Supports ISO 8601 and US/North American week numbering conventions.
About Date & Time Calculators
Date and time calculators handle age computation, date differences, countdown timers, time zone conversion, and calendar arithmetic. These calculations involve non-decimal arithmetic (60 seconds to a minute, 24 hours to a day, variable days per month) that is error-prone to do manually.
Who uses these tools: HR professionals calculating employee tenure, project managers tracking deadlines, lawyers computing limitation periods, travellers coordinating across time zones, and anyone who needs to know exactly how many days between two dates.
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