Hours Between Two Dates Calculator
Count calendar hours, business days, and work hours between two dates. Set workdays, daily schedule, lunch, and federal holidays for an accurate total.
Hours Between Two Dates Calculator
Time Range
Work Schedule
Range crosses a daylight-saving transition. Elapsed time is exact.
Estimates only. Not tax, legal, or payroll advice. Verify against your employer's policy and local holiday calendar.
Track Hours Without the Math
Timeclock44 logs your clock-ins, splits work versus calendar time, and exports timesheets so you never reconcile dates by hand again.
How to Use the Hours Between Two Dates Calculator
Pick a start date and start time, then an end date and end time. The result updates as you type, showing total calendar hours, the count of business days in the range, and a friendly "days / hours / minutes" breakdown.
If you only care about hours worked inside a normal schedule, switch the mode chip to Work hours. The Work schedule card lets you pick which weekdays count, the daily window (default 09:00 to 17:00), and how many unpaid lunch minutes to subtract per business day. Add an hourly rate and pick a currency for an estimated gross pay figure.
Calendar Hours vs. Work Hours: Which Should You Pick?
Calendar mode counts every elapsed hour, including nights and weekends. A Monday 09:00 to Friday 17:00 range is 104 calendar hours. Work hours mode, with Mon to Fri 09:00 to 17:00 and a 30-minute lunch, returns 37.5 hours for the same range, because nights, weekends, and lunch breaks fall outside the window.
Use calendar hours when you need raw elapsed time: SLA durations, lease windows, response-time math. Work hours is the right call when you're reconciling payroll, billing a client, or counting PTO that bumps into a weekend.
Handling Weekends, Holidays, and Daylight Saving Time
Choose any subset of the seven weekdays as your workdays. Toggle Skip US federal holidays to subtract the 11 OPM holidays (New Year's Day, MLK Day, Presidents' Day, Memorial Day, Juneteenth, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving, Christmas) for 2024 through 2027. State and company holidays are not included, so subtract those by hand if they apply.
Daylight saving transitions are handled automatically because the math runs on absolute timestamps. A spring-forward day evaluates to 23 hours and a fall-back day to 25 hours; a small note appears under the result whenever your range crosses one of those boundaries.
Common Use Cases for Hourly Workers and Payroll
Reconciling a pay period that spans a weekend, estimating PTO that crosses a holiday, quoting a multi-day freelance project, figuring out leave hours for an FMLA request: these all lean on the same date-to-date math. For day-to-day clock-in and clock-out tracking, the timecard calculator and biweekly timecard calculator cover the standard pay period. The shift length calculator handles a single shift, and the annual work hours calculator rolls a full year of schedules into one total. If you log hours on the go, the Timeclock44 app keeps the same math in your pocket.
Frequently Asked Questions
Common questions about hours between two dates calculator
How do you calculate the hours between two dates?
Subtract the start timestamp from the end timestamp and divide by 3,600,000 milliseconds. For dates without a time component, multiply the number of full days by 24. This calculator does the math automatically as soon as you fill in both dates and times.
How do I count only work hours between two dates?
Switch to Work hours mode, pick your workdays (typically Mon to Fri), set the daily start and end window (for example 9 to 5), and the calculator clips each day to that window, subtracts unpaid lunch, and ignores weekends or holidays you choose to exclude.
Does this calculator handle daylight saving time?
Yes. The arithmetic uses absolute timestamps, so a spring-forward day correctly evaluates to 23 hours and a fall-back day to 25 hours. A note appears under the result when your range crosses a US DST transition.
What is the difference between calendar hours and business hours?
Calendar hours are the raw elapsed time including nights and weekends (24 times the number of days). Business hours only count time inside your defined workday window on selected workdays. For payroll math, also see our timecard calculator.
How do I convert hours and minutes to decimal hours?
Divide the minute portion by 60 and add it to the hours. For example, 8 hours 30 minutes equals 8 + 30/60 = 8.50 decimal hours, the format most payroll systems require. The payroll time converter handles bulk entries.
Why does the result show fractional days when I picked two whole dates?
Because the calculator uses the start time and end time as well as the dates. A start of Monday 09:00 and end of Wednesday 17:00 is 2 days 8 hours, or 2.33 calendar days.
Which US federal holidays does the calculator skip?
When Skip US federal holidays is on, it excludes the 11 OPM-recognized federal holidays (New Year's Day, MLK Day, Presidents' Day, Memorial Day, Juneteenth, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving, Christmas) for the years 2024 through 2027. State and company-specific holidays must be subtracted manually.
Can I use this for billing a client across multiple days?
Yes. Set your workday window to match the hours you will bill (for example 09:00 to 18:00, Mon to Fri), enter your hourly rate, and the Estimated gross pay line gives the total. For invoicing, also see the billable hours calculator.