Free time duration calculator. Calculate the elapsed time between two clock times or dates, with results in days, hours, minutes, and decimal hours.
A time duration calculator finds the elapsed time between a start and end date/time, expressing the result as days, hours, and minutes, as well as a single decimal-hours figure useful for billing, payroll, or time tracking.
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Time Duration Calculator
Calculating the time between two points sounds simple, but doing it by hand gets error-prone once you're crossing midnight, spanning multiple days, or converting minutes into a decimal fraction of an hour. This calculator handles all of that automatically from a start and end date/time.
The result is shown two ways: a human-readable breakdown of days, hours, and minutes, and a single decimal-hours figure ā the format most commonly needed for billing, payroll, and time tracking, where a fraction like 1.75 hours is far more useful than "1 hour 45 minutes" for multiplying against an hourly rate.
Decimal Hours
Hourly rates are multiplied against time worked, and that math only works cleanly with decimal numbers ā 1 hour 30 minutes at $50/hour isn't obviously $75 until you convert it to 1.5 hours. This is why invoices, timesheets, and payroll systems almost universally use decimal hours rather than a colon-separated hours-and-minutes format.
The conversion itself is simple ā minutes divided by 60 ā but doing it manually for every entry on a timesheet is tedious and error-prone. This calculator does the conversion automatically as part of computing the total elapsed duration.
Multi-Day Spans
A duration that crosses midnight ā like a shift starting at 10 PM and ending at 6 AM ā requires correctly accounting for the date rollover, not just subtracting clock times, which would produce a negative or nonsensical result. This calculator uses full date and time values specifically to handle that correctly.
The same logic extends naturally to spans of several days, weeks, or longer ā useful for measuring project timelines, subscription periods, or any duration where the start and end aren't on the same day.
Practical Precision
This calculator measures duration down to the second based on the minute-level precision of the date and time inputs, which is more than sufficient for virtually all everyday, billing, and scheduling use cases. Second-level precision matters mainly for the underlying total-seconds figure, useful for technical or scientific applications.
For everyday use ā timesheets, meeting lengths, or figuring out how long until an event ā the days/hours/minutes breakdown and decimal-hours total cover the vast majority of practical needs without any manual conversion.
Practical Use Cases
Calculating billable hours
Converting a start and end time into decimal hours for client invoicing.
Measuring meeting or event length
Finding the exact duration between a start and end time for scheduling purposes.
Tracking freelance or contract work
Logging time spent on a task as a precise decimal-hours figure.
Planning travel or shift schedules
Calculating elapsed time across an overnight shift or multi-day trip.
Estimating project or task duration
Finding the total time between a project's start and end dates.
Decimal hours express time as a single number instead of hours and minutes ā for example, 1 hour 30 minutes becomes 1.5 hours. This format is standard for hourly billing, payroll, and timesheets, since it's easier to multiply by an hourly rate than a combined hours-and-minutes figure.
Yes ā enter any start and end date and time, and the calculator handles multi-day spans correctly, showing the full elapsed duration in days, hours, and minutes, plus the total in decimal hours.
Yes ā since the calculation is based on your device's local time for both the start and end values, any daylight saving transition between them is automatically reflected in the elapsed duration.
A time card calculator is built for weekly payroll totals across multiple clock-in and clock-out entries, often with break deductions and overtime rules. This tool is a simpler point-to-point duration calculator for any two dates or times, without payroll-specific logic.
Yes, though for calculating age in years or the exact time until a specific future date, a dedicated date difference or age calculator may present the result in a more relevant format (like years and months) rather than total hours.