Time Between Two Times Calculator

A time between two times calculator finds the duration from one clock time to another, in hours and minutes. From 9:00 AM to 5:00 PM is 8 hours, and with a 30-minute break the working time is 7 hours 30 minutes. From 8:15 AM to 12:45 PM is 4 hours 30 minutes, and from 10:00 PM to 6:00 AM is 8 hours, because the span crosses midnight. The time calculator above finds any span in its between-times mode, and this page explains the subtraction, the break, and the midnight rule.

The subtraction is a minutes subtraction with a borrow: convert both times to minutes since midnight, subtract, and convert back. The break is subtracted once, from the total, and an overnight span needs 1,440 minutes added to the end time before subtracting, because the end belongs to the next day. This page works through five spans, shows the break and midnight cases, and explains the decimal-hours conversion for pay.

How Time Arithmetic Works: Adding, Subtracting, and Pay

Time arithmetic is base-60 arithmetic, which is why it feels unfamiliar: 60 minutes make an hour, so 2 hours 45 minutes plus 1 hour 30 minutes is 4 hours 15 minutes, not 3 hours 75 minutes, because the 75 minutes carry one hour. The reliable method is to convert everything to minutes, add or subtract, and convert back: 165 + 90 = 255 minutes, and 255 ÷ 60 = 4 hours with 15 minutes left over. The calculator above does this conversion for you, and it also converts the result to decimal hours, so 7 hours 30 minutes is 7.50 hours for pay and billing.

The time between two clock times is a subtraction with the same carry rule. From 9:00 AM to 5:00 PM is 8 hours, and with a 30-minute break the working time is 7 hours 30 minutes. Overnight spans need one extra step: from 10:00 PM to 6:00 AM is 8 hours, because the clock passes midnight, so the end time belongs to the next day. A five-day week of 9:00 AM to 5:00 PM with a 30-minute break each day totals 37 hours 30 minutes, which is 37.50 decimal hours, and at $25 an hour that is $937.50 of pay.

The United States time standards behind these calculations are maintained by the National Institute of Standards and Technology, whose time and frequency work is published at nist.gov. The arithmetic on this page is the same base-60 arithmetic that clocks, timesheets, and payroll systems all use.

Step 1 — Convert Every Duration to Minutes

Multiply the hours by 60 and add the minutes: 2 hours 45 minutes is 165 minutes, and 1 hour 30 minutes is 90 minutes. Working in minutes removes the base-60 confusion entirely, and it is the step the calculator performs internally.

Step 2 — Add or Subtract the Minutes

Add the minute totals: 165 + 90 = 255 minutes. For a time between two clock times, subtract the start minutes from the end minutes, adding 1,440 minutes (24 hours) to the end first if the span crosses midnight.

Step 3 — Convert Back to Hours and Minutes

Divide by 60: 255 ÷ 60 = 4 hours with 15 minutes left over, so the answer is 4 hours 15 minutes. For pay, divide the total minutes by 60 to get decimal hours: 450 minutes is 7.50 hours, and 7.50 × $25 = $937.50.

Worked Examples: Time Between Two Times

Each row gives two clock times, the span, and the note that explains it.

The third row is the overnight case: 10:00 PM is 1,320 minutes since midnight, 6:00 AM is 360 minutes, and adding 1,440 minutes to the end gives 1,800, so the span is 1,800 − 1,320 = 480 minutes, which is 8 hours. The fourth row shows a span with uneven minutes: 7:30 AM is 450 minutes, 3:45 PM is 945 minutes, and 945 − 450 = 495 minutes, which is 8 hours 15 minutes. Try the same times in the calculator above and confirm each span.

How to Use the Time Calculator

The calculator has modes for adding and subtracting durations, for the time between two clock times, and for a full weekly timesheet with daily breaks and an hourly rate. Enter your times and it shows hours, minutes, decimal hours, and pay.

1. Choose the mode. Add durations for totals, between two times for a single span, or timesheet for a full week with a break each day.
2. Enter the hours and minutes. The default durations add to a clean example; change any field and the total updates immediately.
3. Set the break for timesheet mode. The default 30-minute daily break is subtracted from each day before the weekly total is computed.
4. Enter an hourly rate to see pay. The calculator multiplies decimal hours by your rate, so 37.50 hours at $25 an hour shows $937.50.
5. Read the decimal hours. Payroll and billing use decimal hours, so 7 hours 30 minutes is 7.50 hours, not 7.30, and the calculator shows both forms.

The Same Span in Hours, Minutes, and Decimal Hours

A span is useful in three forms: hours and minutes for people, total minutes for arithmetic, and decimal hours for pay. This table converts the example spans.

Common Mistakes With Time Arithmetic

Time is the only everyday arithmetic that runs in base 60, and that is exactly where the mistakes come from.

• Writing 7.30 for 7 hours 30 minutes. In decimal hours, 30 minutes is 0.50, not 0.30, so 7 hours 30 minutes is 7.50 hours. The .30 error underpays by 12 minutes an hour.
• Forgetting to carry 60 minutes. 2 hours 45 minutes plus 1 hour 30 minutes is 4 hours 15 minutes, not 3 hours 75 minutes, because 75 minutes carries an hour.
• Forgetting midnight. A shift from 10:00 PM to 6:00 AM is 8 hours, not negative 16, because the end time belongs to the next day.
• Subtracting the break twice. A 30-minute break is subtracted once per day; subtracting it from the total as well as from each day double-counts it.
• Mixing 12-hour and 24-hour times. 5:00 PM is 17:00, and subtracting 9:00 from 5:00 without the PM gives a wrong or negative answer.

Where You Will Use Time Arithmetic

Adding hours, measuring spans, and totalling timesheets are the arithmetic of work, travel, and everyday planning.

• Timesheets and payroll. A week of 9:00 AM to 5:00 PM with a 30-minute break is 37 hours 30 minutes, and the pay follows from the decimal hours.
• Shift planning. The gap between a shift’s start and end, minus breaks, is the paid time, and it must be right before the roster is published.
• Travel. The time between departure and arrival, across time zones and overnight, is the journey length, and it decides connections and rest.
• Project tracking. Adding task durations in hours and minutes shows the total effort, and converting to decimal hours prices it.
• Daily routines. Adding a workout, a commute, and a lunch break shows how much of the day is spoken for, and how much is left.

Overnight Spans and the Midnight Rule

A span that crosses midnight is the one people get wrong most often, because the end time is numerically smaller than the start time. The rule is simple: if the end time is earlier than the start time, add 24 hours to the end before subtracting. From 10:00 PM to 6:00 AM, the end plus 24 hours is 30:00, and 30:00 minus 22:00 is 8 hours. From 11:30 PM to 2:15 AM, the end plus 24 hours is 26:15, and 26:15 minus 23:30 is 2 hours 45 minutes. The calculator handles the midnight carry automatically, so an overnight span needs no special input.

Tips for Accurate Results

Time arithmetic rewards a steady method. These habits keep the minutes honest.

1. Always work in minutes. Convert to minutes, do the arithmetic, and convert back; it removes the base-60 confusion at a stroke.
2. Write AM and PM explicitly. A 12-hour time without AM or PM is ambiguous, and the ambiguity always costs an hour or twelve.
3. Record the break once per day. In a timesheet, the break belongs to the day it was taken, not to the weekly total.
4. Use decimal hours for money. Multiply decimal hours by the rate, never hours-and-minutes notation, or the pay will be wrong.
5. Check overnight spans by adding. From 10:00 PM, add the hours forward past midnight to 6:00 AM and count: 2 hours to midnight plus 6 hours is 8.

Time Quick Answers

These are the time answers people look up most often, each one verified against the calculator above.

Related tools on this site: the main time calculator, salary calculator, days calculator, date difference calculator, and the time calculator again whenever you need a fresh check.

Frequently Asked Questions

How do I find the time between two times?

Convert both times to minutes since midnight, subtract the start from the end, and convert back to hours and minutes. From 9:00 AM to 5:00 PM, that is 1,020 − 540 = 480 minutes, which is 8 hours. The calculator above does the subtraction for you.

How long is 9:00 AM to 5:00 PM with a 30-minute break?

The span is 8 hours, and subtracting the 30-minute break gives 7 hours 30 minutes of working time. A five-day week of that pattern totals 37 hours 30 minutes, which is 37.50 decimal hours.

How do I calculate time across midnight?

Add 24 hours to the end time before subtracting. From 10:00 PM to 6:00 AM, the end becomes 30:00, and 30:00 minus 22:00 is 8 hours. The calculator applies this rule automatically for overnight spans.

What is the time between 8:15 AM and 12:45 PM?

It is 4 hours 30 minutes. In minutes, 12:45 PM is 765 minutes since midnight and 8:15 AM is 495 minutes, so the span is 765 − 495 = 270 minutes, which is 4 hours 30 minutes.

How do I convert the span to decimal hours for pay?

Divide the total minutes by 60: 450 minutes is 7.50 hours, and 495 minutes is 8.25 hours. Multiply the decimal hours by the hourly rate to get the pay for the span.

Disclaimer: This calculator is for general information only. Pay figures are estimates from the hours and rate you enter; actual pay is governed by your employer, your contract, and applicable labour law, including overtime rules.