Time & Date Calculators
Date difference calculators, age calculators, business day counters, time zone converters, and work hour trackers. When you need to know exactly how many days, hours, or business days between two dates.
- ✓Date math: add/subtract days, date difference, business days
- ✓Time tracking: work hours, time cards, hours calculator
- ✓Conversion: time zones, military time, Unix timestamps
- ✓Utilities: age calculator, countdown timer, week numbers
Most used: Age Calculator, Date Difference Calculator, Time Zone Converter
Try any of the 15 time & date calculators below — or get one free for your AI.
Every calculator on this page is free to use right now. You can also download any one as a Claude skill file (free with email) to chat with it in Claude Code, ChatGPT, or any AI platform. Or get the full Time & Scheduling Pack for $29.
Common workflows in this category
Click any scenario to jump into the calculator with the example pre-loaded.
15 free calculators
Age Calculator
Calculate your exact age down to the day, month, and hour. Get precise age calculations instantly.
Business Days Calculator
Calculate working days between dates, excluding weekends and holidays. Perfect for project timelines and deadlines.
Countdown Timer
Calculate days, hours, and minutes remaining until your event, holiday, deadline, or special date.
Date Add/Subtract Calculator
Add or subtract days, weeks, months, or years from any date instantly. Perfect for deadline planning.
Date Difference Calculator
Calculate the exact number of days, weeks, or months between two dates instantly.
Hours Calculator
Calculate the exact number of hours and minutes between two times instantly, including across midnight.
Military Time Converter
Convert between 12-hour AM/PM and 24-hour military time formats instantly. Easy reference guide included.
Snooze Calculator
Calculate your actual wake-up time based on alarm time, snoozes, and snooze duration.
Stopwatch and Timer
Simple, accurate online stopwatch for timing activities. Also includes countdown timer functionality.
Sunrise/Sunset Calculator
Calculate accurate sunrise and sunset times for any location and date. Plan outdoor activities with precision.
Time Card Calculator
Calculate total weekly hours from time card clock-in and clock-out entries. Simple, accurate timesheet totals.
Time Zone Converter
Instantly convert time between any two cities and time zones worldwide. Account for daylight saving time.
Unix Timestamp Converter
Convert Unix epoch timestamps to human-readable dates and times instantly. Support milliseconds and timezones.
Week Number Calculator
Find the ISO week number for any date. See week start and end dates instantly.
Work Hours Calculator
Calculate total hours worked in a week or pay period. Perfect for accurate timesheets and payroll.