Time Calculator

Hours between two times · Add time · Subtract time · 12hr & 24hr formats

Quick Answer

Hours between two times = end − start; if the end is earlier, add 24 hours for an overnight shift. 9:00 AM to 5:00 PM = 8 hours, and 10:00 PM to 6:00 AM = 8 hours across midnight. Most countries log shifts on a 24-hour clock, while the US and UK commonly use 12-hour AM/PM.

Enter 12-hour (9:30 AM) or 24-hour (17:30) format

Quick examples

9:00 AM → 5:30 PM
8 hrs 30 mins
8:45 AM → 12:00 PM
3 hrs 15 mins
9:00 PM → 6:00 AM
9 hrs (overnight)
7:30 AM → 7:30 PM
12 hrs exactly

Common Work Schedule Calculations

Shift Hours Common In
9:00 AM – 5:00 PM 8 hrs Standard US/UK office shift
9:00 AM – 5:30 PM 8 hrs 30 mins With 30-min lunch break
8:00 AM – 4:00 PM 8 hrs Early shift
10:00 PM – 6:00 AM 8 hrs (overnight) Night shift — crosses midnight
7:00 AM – 7:00 PM 12 hrs US hospital/healthcare shifts
6:00 AM – 6:00 PM 12 hrs Manufacturing / factory shifts

🌍 Work Hours by Country

Legal maximum weekly hours vary significantly:

🇺🇸 US
40 hrs/week
FLSA standard
🇬🇧 UK
48 hrs/week
Working Time Directive (opt-out available)
🇩🇪 Germany
48 hrs/week
8 hrs/day max by law
🇫🇷 France
35 hrs/week
Famously short workweek
🇯🇵 Japan
40 hrs/week
60-hr cap inc. overtime
🇦🇺 Australia
38 hrs/week
NES standard

Related Calculators

📅 Date Difference Calculator →
Days between two dates
🎂 Age Calculator →
Exact age in years, months, days
🕐 Hours Calculator →
Work hours and timesheets
⏳ Countdown Calculator →
Days until an event
Cite this page APA · MLA · BibTeX

APA

WorldCalculators.org. (n.d.). Time Calculator — Hours Between Times, Add/Subtract Hours. https://worldcalculators.org/calculators/time-calculator/

MLA

“Time Calculator — Hours Between Times, Add/Subtract Hours.” WorldCalculators.org, worldcalculators.org/calculators/time-calculator/.

BibTeX

@misc{worldcalculatorscalculatorstimecalculato,
  title        = {Time Calculator — Hours Between Times, Add/Subtract Hours},
  author       = {{WorldCalculators.org}},
  year         = {n.d.},
  howpublished = {\url{https://worldcalculators.org/calculators/time-calculator/}}
}

Figures change when tax years or guidance change. Cite the date shown and link the page so readers see the current version.