Time Calculation Tools
A beautiful collection of smart calculators for all your time-related questions. Select a tool to get started instantly.
Data & Conversion
Decimal Hours Converter
Convert decimal hours to hours/minutes format and vice-versa.
Epoch & Unix Timestamp Converter
Convert Unix timestamps to and from human-readable dates.
Julian Day Calculator
Convert a calendar date to an Ordinal Date (day of year) and Julian Day Number.
Time Format Converter
Convert time between 24-hour and 12-hour (AM/PM) formats.
Time Unit Converter
Convert time between seconds, minutes, hours, and days.
Date & Lifecycle
Age Calculator
Find your exact age in years, months, and days.
Baby Age Calculator
Calculate a baby's age in weeks/months, perfect for tracking milestones.
Birthday Calculator
Find out how many days are left until your next birthday and on which day of the week it falls.
Holiday Countdown
Count down the days to popular holidays like Christmas and New Year's Day.
Pregnancy Due Date Calculator
Estimate your due date and track your pregnancy progress.
Retirement Countdown Calculator
Calculate the time remaining until your retirement.
Health & Wellness
Scheduling & Planning
Academic Term Calculator
Determine the end date of a semester or academic term based on a start date and duration.
Deadline Calculator
Calculate a deadline by adding a duration to a start date, optionally excluding weekends.
Driving Hours Calculator
Calculate your total driving time for a trip, including rest breaks.
Flight Travel Planner
Plan multi-leg flights with layovers and time zone changes.
Meeting Planner
Schedule meetings across multiple time zones with ease.
Next Occurrence Calculator
Find the date of the next event in a recurring series (e.g., every X weeks).
School Timetable
Generate a weekly schedule for school classes and subjects.
Time Zone Change Viewer
Check for upcoming Daylight Saving Time changes in a specific time zone.
Time Zone Difference
See the current time and difference between two time zones.
Travel Time Calculator
Calculate your arrival time based on departure and travel duration.
Week Number Calculator
Find the week number of the year for a given date.
Weekday Checker
Quickly check if a given date is a weekday or a weekend.
Weekdays Between Dates
Count the number of business days (weekdays) between two dates.
Time & Timers
Cooking Timer
A multi-step timer for recipes that you can create and share.
Countdown Timer
Create a live countdown to any future date and time.
Hours Between Times
Measure the duration between two times on the same day, with an optional break.
Interval Timer
Set a custom countdown for a specific duration.
Pomodoro Timer
Boost your productivity with the Pomodoro Technique of work and break intervals.
Stopwatch
Measure elapsed time with precision, including lap tracking.
Time Calculator
Perform arithmetic operations on time values (add, subtract, multiply, divide).
Time Difference
Calculate the duration between two points in time, across different time zones.
Work & Payroll
Meeting Duration Calculator
Calculate the total time spent in a meeting based on start and end times.
Payroll Period Calculator
Generate a schedule of pay periods and pay dates based on a pay frequency.
Project Time Tracker
Log hours worked per project, with multiple project support and CSV export.
Shift Time
Determine your net payable hours for a shift after deducting unpaid breaks.
Weekly Work Hours
Log your daily work hours to calculate your total weekly and overtime hours.
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