Hours Calculator

Use the calculators below to find the number of hours and minutes between two times. For a full time card, please use the Time Card Calculator.

Hours Between Two Times

12-hour format 24-hour format

Start Time:

End Time:

Duration: ?

Hours Between Two Dates

Start Time:
End Time:

Duration: ?

An hour is most commonly defined as a period of time equal to 60 minutes, where a minute is equal to 60 seconds, and a second has a rigorous scientific definition. There are also 24 hours in a day. Most people read time using either a 12-hour clock or a 24-hour clock.

12-hour clock:

A 12-hour clock uses the numbers 1-12. Depending on the clock being used, most analog clocks or watches may not include an indication of whether the time is in the morning or evening. On digital clocks and watches, "AM" stands for ante meridiem, meaning "before midday," while "PM" stands for post meridiem, or "after noon." By convention, 12 AM denotes midnight, while 12 PM denotes noon. Using the terms "12 midnight" and "12 noon" can remove ambiguity in cases where a person may not be accustomed to conventions.

24-hour clock:

A 24-hour clock typically uses the numbers 0-23, where 00:00 indicates midnight, and a day runs from midnight to midnight over the course of 24 hours. This time format is an international standard, and is often used to avoid the ambiguity resulting from the use of a 12-hour clock. The hours from 0-11 denote what would be the AM hours on a 12-hour clock, while hours 12-23 denote the PM hours of a 12-hour clock. In certain countries, 24-hour time is referred to as military time, since this is the time format used by militaries (and other entities) around the world, where unambiguous time measurement is particularly important.

Hours in different time periods

Description	Hours
Hours in a day	24
Hours in a week	168
Hours in a month	672 for a 28-day month 696 for a 29-day month 720 for a 30-day month 744 for a 31-day month 730.5 on average
Hours in a year	8,760 for a 365-day year 8,784 for a 366-day year 8,766 on average
Hours in a decade	87,648 for a 2-leap-year decade 87,672 for a 3-leap-year decade 87,660 on average
Hours in a century	876,600

How to Use the Hours Calculator?

Enter Start & End Time – Input the time range to calculate the total hours.

Select Time Format – Choose between 12-hour or 24-hour format.

Get Instant Results – The calculator provides precise hour calculations.

Common Questions About Hours Calculation

How do I calculate the total hours worked?

Simply enter your start and end time, and our calculator will instantly compute the total hours worked, including break durations if applicable.

Can I calculate hours for overnight shifts?

Yes! Our tool allows you to calculate hours across multiple days, including shifts that span midnight.

How do I convert hours into minutes and seconds?

Our calculator lets you convert hours into minutes, seconds, or even milliseconds for precise time tracking.

How does the 12-hour vs. 24-hour clock affect calculations?

The 12-hour clock uses AM/PM notation, while the 24-hour clock runs from 00:00 to 23:59. Our calculator supports both formats for convenience.

Can I calculate billable hours for freelancers and contractors?

Yes! Use our calculator to track billable hours for accurate invoicing and payroll management.

Use Cases for the Hours Calculator

Work & Productivity Management

Calculate total working hours, overtime, and break durations.

Optimize time tracking for freelancers, employees, and businesses.

Payroll & Billing Calculations

Determine billable hours for accurate invoicing.

Track employee work hours for payroll processing.

Event Planning & Scheduling

Calculate the duration of meetings, webinars, and appointments.

Plan travel schedules by determining total hours between departure and arrival.

Educational & Exam Preparation

Manage study sessions by calculating time spent on different subjects.

Estimate time per question for exams to improve efficiency.

Scientific & Technical Applications

Convert time units for physics and engineering calculations.

Compute precise time intervals for research and experiments.

Why Use the Hours Calculator at CalculatorJet.com??

At CalculatorJet.com, we provide accurate and user-friendly tools to simplify everyday calculations. Our Hours Calculator ensures precision in tracking work hours, converting time units, and managing schedules. Whether for personal, professional, or educational purposes, our tool helps you stay organized and efficient.

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