Free Date & Time 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.