Hours Calculator

Calculate elapsed hours and minutes between clock times across midnight.

Start Time

End Time

Crosses midnight into next day (+24 hours)

How It Works

The Hours Calculator computes elapsed time between two clock times or adds/subtracts a duration from a start time.

It seamlessly handles crossing midnight, provides decimal hours for payroll and invoicing, and formats results in both 12-hour AM/PM and 24-hour military standards.

Formula & Calculation

Elapsed Time & Decimal Hours Formula

Elapsed Minutes = (EndMinutes − StartMinutes + 1440) % 1440

StartMinutes=Minutes elapsed since midnight for start time

EndMinutes=Minutes elapsed since midnight for end time

1440=Total minutes in a 24-hour day

Adding 1,440 minutes ensures overnight shifts crossing midnight calculate accurately without negative numbers.

Decimal Hours for Payroll

Decimal Hours = Hours + (Minutes / 60)

Hours=Whole hours portion

Minutes=Remaining minutes divided by 60

For example, 8 hours and 15 minutes equals 8.25 decimal hours; 8 hours and 45 minutes equals 8.75.

Step-by-Step Example

Example 1: Daytime Shift (9:00 AM to 5:30 PM)

Calculate elapsed work hours for a standard business day:

Step 1: Convert clock times to minutes from midnight: 09:00 = 540 min; 17:30 = 1,050 min→ 1,050 − 540 = 510 min

Step 2: Convert to hours and minutes: 510 / 60 = 8 with 30 remaining→ 8 hours, 30 minutes

Step 3: Convert to decimal hours: 8 + (30 / 60)→ 8.50 decimal hours

Total elapsed time is 8 hours and 30 minutes (8.50 decimal hours).

Example 2: Overnight Shift (10:15 PM to 6:45 AM)

Calculate hours for a night shift crossing midnight:

Step 1: Account for midnight transition: 22:15 = 1,335 min; 06:45 next day = 405 + 1,440 = 1,845 min→ 1,845 − 1,335 = 510 min

Step 2: Convert to hours and minutes: 510 / 60 = 8 hours, 30 minutes→ 8h 30m

Total overnight duration is 8 hours and 30 minutes (8.50 decimal hours).

Assumptions & Edge Cases

Midnight Crossing Assumption: When the end time is numerically earlier than the start time, the calculator assumes the event concluded on the following calendar day within a 24-hour cycle.
Unpaid Meal Breaks: This tool calculates gross elapsed clock time. To automatically deduct lunch breaks and sum a multi-day weekly schedule, use our dedicated Working Hours Calculator.

Frequently Asked Questions

How do I convert minutes to decimal hours for timesheets?

Divide minutes by 60. Common equivalents: 15 min = 0.25 hrs, 30 min = 0.50 hrs, 45 min = 0.75 hrs.

Working Hours Calculator

Calculate billable working hours across date ranges accounting for shift times and breaks.

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