Live Hours Calculator
It subtracts a start time from an end time and deducts an optional break, including overnight spans.
8 hr 0 min
BulkCalculator Time Tools
Hours Calculator
Free hours calculator between two times with optional break deduction for shifts, schedules and invoices.
How to use Hours Calculator
- Open the Hours Calculator page and use the default example if you want a quick test.
- Enter start time, end time and break minutes in the tool panel.
- Press the primary action button or use the listed keyboard shortcut when available.
- Read the result as total payable or elapsed hours and minutes, then copy, export or print it if needed.
Formula and algorithm
Duration equals end minutes minus start minutes, plus 24 hours if the end is after midnight, minus break minutes.
This tool runs in your browser. If the tab is backgrounded or the device sleeps, visible updates or alerts may be delayed. Notifications and Wake Lock reduce that risk where supported, but they are not a guarantee.
Worked example
9:00 AM to 5:30 PM, lunch 30 min. The expected output is 8 hr 0 min.
{
"tool": "Hours Calculator",
"input": "9:00 AM to 5:30 PM, lunch 30 min.",
"output": "8 hr 0 min."
}Use cases
- Shift planning
- Freelance invoices
- Class schedules
- Meeting duration checks
- Break deductions
Pro tips and gotchas
- Use 24-hour inputs when the shift crosses noon or midnight.
- Enter unpaid breaks in minutes.
- Overnight shifts are supported.
- Round only if your workplace requires it.
- Use the time card page for weekly totals.
Frequently Asked Questions
How many hours between two times calculator
Enter the start time and the end time. The calculator returns the duration in hours and minutes. So from 9:00 AM to 5:30 PM, you get 8 hours 30 minutes. Crosses midnight too — 10:00 PM to 2:00 AM = 4 hours, with the calculator detecting the day rollover automatically. Useful for shift logging, meeting durations, study session tracking, and any "how long did that take?" calculation that comes up at the end of the day.
How to calculate hours worked in a day
Enter your start time and end time. Then enter the unpaid break duration (lunch, coffee breaks, anything that doesn't count toward paid hours). The calculator subtracts the break and shows the actual worked hours. So 9:00 AM to 6:00 PM with a 60-minute lunch = 8 hours of paid work. Useful for daily timesheet logging, freelance billing, and figuring out if you actually did 40 hours this week or just close.
How many hours from 9 to 5 with lunch
9 AM to 5 PM is 8 hours total. Subtract a 1-hour lunch and you've got 7 hours of paid work. With a 30-minute lunch, it's 7 hours 30 minutes. The calculator does this in one step — enter 9:00 AM start, 5:00 PM end, set break duration, hit Calculate. So when someone says they "work 9 to 5", the actual paid hours depend entirely on the break length, which is why the calculator's break field exists.
How to subtract lunch break from hours worked
Enter the start and end times of your shift, then enter the lunch break duration in the break field. The calculator subtracts the break automatically and shows the net worked hours. So 8:00 AM to 5:00 PM with a 45-minute lunch = 8 hours 15 minutes of actual work. Some workplaces pay through lunch, in which case skip the break field and you get the full elapsed time. Set it up to match your employer's rules.
How many hours until a specific time today
Enter the current time as the start and your target time as the end. The calculator returns the duration remaining. So if it's 10:00 AM and you want to know how long until 6:00 PM, the result is 8 hours. If the target time has already passed today, the calculator rolls forward to tomorrow automatically (or shows zero, depending on settings). Useful for waiting for meetings, deadlines, or "when can I leave?" countdowns.
How to calculate total hours and minutes online
Enter the start and end times. The calculator returns the duration in hours and minutes — so 9:15 AM to 4:50 PM = 7 hours 35 minutes. The output is also shown in decimal hours (7.58) for payroll and freelance billing. The dual output saves you the conversion step. Useful for any time-span calculation: shifts, meetings, study sessions, drive times, anything you'd otherwise count on your fingers or work out with mental arithmetic.
How to convert hours and minutes to decimal hours
Divide the minutes by 60 and add to the hours. So 1 hour 30 minutes = 1.5 hours, 2 hours 15 minutes = 2.25 hours, 8 hours 45 minutes = 8.75 hours. The calculator shows decimal hours alongside the standard hours-and-minutes format whenever you compute a duration. Useful for payroll systems, freelance billing software, and project tracking tools that expect decimal time entries rather than the human-readable format.
Glossary
- UTC
- Coordinated Universal Time, the reference time standard used for offsets and date math.
- DST
- Daylight Saving Time, a seasonal clock change that can affect wall-clock schedules.
- IANA time zone
- A named time zone such as America/New_York used by browsers for DST-aware rendering.
- Tab-title timer
- A timer state shown in the browser tab title so it remains visible while multitasking.
- Wake Lock
- A browser feature that can ask a device to keep the screen awake during active timing.
- localStorage
- Browser storage used here for settings and saved tool state on the same device.
- Input format
- Start time, end time and break minutes.
- Output format
- Total payable or elapsed hours and minutes.
References and sources
- ISO 8601 for week-number rules.
- 5 U.S.C. section 6103 for US federal holidays.
- IANA Time Zone Database for time zone identifiers.
- The Pomodoro Technique, Francesco Cirillo, 1987 for Pomodoro method.
- US Department of Labor FLSA for overtime context.
- NIST Time and Frequency Division for time-keeping standards.