Use the calculator below to find the hours, minutes, and seconds between two times, or calculate the full duration between two dates including the time of day.
Enter start and end times to calculate the duration between them.
Enter times and click Calculate to see the duration.
Use this time and date duration calculator to find out the number of days, hours, minutes, and seconds between the times on two different dates.
Enter dates and times, then click Calculate.
Two modes, one idea: subtract one moment from another and express the gap in days, hours, minutes, and seconds. In the first mode you give two clock times on the same day; in the second you give two full dates with times, and the gap can run across weeks or years.
Everything runs in the browser. Nothing you type is sent anywhere, and results update as you change a field, which makes the tool usable for quick checks without a round trip.
Clock arithmetic is ordinary subtraction with a base of 60 instead of 10, which is why it goes wrong so easily. The method below works for two times on the same day.
Two worked cases:
Direct. 13:57 minus 09:22. Minutes: 57 − 22 = 35. Hours: 13 − 9 = 4. Result 4 h 35 min.
With borrowing. 12:57 minus 09:58. Borrow an hour, so 12:57 becomes 11:117. Minutes: 117 − 58 = 59. Hours: 11 − 9 = 2. Result 2 h 59 min.
If the end time is earlier than the start time, the interval has passed midnight. Add 24 hours to the end time and subtract again: 06:00 minus 22:00 becomes 30:00 minus 22:00, or 8 hours.
The 12-hour clock runs from 1 to 12 twice a day and needs AM or PM to say which pass it is. Midnight is 12:00 AM and noon is 12:00 PM, a convention that catches people out precisely because both look like "12".
The 24-hour clock runs once, from 00:00 to 23:59, and needs no suffix. Converting is mechanical: 12 AM becomes 00:00, hours 1 to 11 AM stay as they are, 12 PM stays 12:00, and every PM hour from 1 to 11 gains 12.
The calculator accepts either, so the format only matters when you check the result by hand. For anything involving schedules, transport, or records kept across midnight, 24-hour input removes an entire class of error. For adding and subtracting intervals rather than measuring between two moments, use the Time Calculator.
Most uses are ordinary: a shift, a film, a workout, a commute.
These are the cases worth doing by hand once so the base-60 borrowing makes sense. After that, the calculator is faster and less error-prone, particularly when seconds are involved.
For a same-day interval, enter the start and end times in the hour, minute, and second fields and pick AM or PM for each. The duration appears as you type. The "Now" control fills the fields with the current system time, which is useful when you are timing something as it happens.
For anything longer than a day, switch to the date section: choose the two dates and the times on each, and the result comes back in days, hours, minutes, and seconds. Dates default to today, so nearby calculations need only one change.
Two small controls help with checking: the swap button reverses start and end so you can confirm the interval is the same in both directions, and the clear button resets a section. If a swapped calculation gives a different answer, the inputs disagree in a way worth finding.
Timesheets are the single most common use of this tool, and also where small errors cost money. A shift from 9:00 AM to 5:30 PM is 8 hours 30 minutes of elapsed time, but the paid figure is lower once an unpaid lunch is removed.
Overnight shifts need the midnight handling described below: 10:00 PM to 6:00 AM is 8 hours, not a negative number. For a full pay period, run each shift separately and add them, or use the date mode for one long span when you only need a total.
Payroll systems often round to the nearest quarter hour or tenth of an hour, and some employers apply a rule that shifts a few minutes either way to the nearest quarter. Compute the exact duration first, then apply the rounding rule your employer publishes — rounding before subtracting breaks is how totals drift. The Hours Calculator handles break deductions directly.
A start time later than the end time means the interval passed through midnight. Subtracting directly gives a negative number, which is the signal to add 24 hours to the end time before trying again.
10:00 PM to 6:00 AM is the standard example: 22:00 to 30:00, or 8 hours. The same trick covers a late-night event ending after midnight, a server window that runs overnight, and any shift that starts on one calendar day and finishes on the next.
The calculator applies this correction automatically, so the only thing to check is whether the crossing was intended. If you actually meant a 20-hour interval rather than an 8-hour one, the dates need to be entered explicitly in the date section.
The same subtraction serves very different fields. Transport planning needs journey and connection times. Clinical settings need infusion and observation intervals. Schools need period lengths. Kitchens need timings counted back from a serving moment.
In sport it is split times and rest intervals; in broadcasting it is runtime and segment length; in software it is timeouts, cache lifetimes, and log windows. Each looks different on the surface and reduces to the same operation: how much time sits between these two instants.
For calendar arithmetic rather than clock arithmetic — adding days to a date, finding a weekday — the Date Calculator is the better fit.
Travel planning is mostly a chain of durations: flight time, connection buffer, transfer to the hotel. Adding them up by hand is where itinerary mistakes come from, particularly when a leg crosses a time zone or midnight.
For multi-day trips, the date mode gives the total span in one step. A trip leaving 1 June at 8:00 AM and returning 10 June at 10:00 PM covers 9 days and 14 hours — useful for visa limits, accommodation nights, and per-diem calculations.
Event planning uses the same arithmetic at a smaller scale: setup, each session, breaks, teardown. Running the segments through the calculator once produces a schedule that actually fits the venue's hours, rather than one that looks right until the first overrun.
The calculator works with whatever clock times you enter. It does not know where those times were recorded, so it cannot correct for time zones. The fix is to convert both endpoints to the same zone first.
Suppose a call starts at 10:00 AM Eastern and ends at 2:00 PM Pacific. In Eastern terms that is 10:00 AM to 5:00 PM, or 7 hours — not the 4 hours the raw numbers suggest.
Daylight saving adds a second layer. A span that crosses a spring-forward date is an hour shorter than the wall-clock difference implies; one that crosses a fall-back date is an hour longer. Entering both endpoints in UTC avoids the problem entirely, which is why logs and systems that care about exact durations record in UTC. For the current official time in the United States, see time.gov from NIST and the U.S. Naval Observatory.
Check the AM/PM setting first. It is the most common source of a result that is exactly 12 hours out, and it is easy to miss on a form that pre-selects a value.
Include seconds when they matter and leave them at zero when they do not. Mixing a value with seconds against one without silently introduces up to 59 seconds of error, which is irrelevant for a lunch break and significant for a race time or a log analysis.
Verify dates in the long mode. A day either side changes the answer by 24 hours, and a wrong year changes it by hundreds. Picking from the date control rather than typing avoids most format confusion.
Finally, sanity-check the magnitude. If you expected roughly an hour and got thirteen, the problem is almost always AM/PM; if you expected eight hours and got minus sixteen, the problem is midnight.
Swapped AM/PM. Shifts the result by 12 hours. Noon and midnight are the usual casualties; treat 12:00 AM as the start of the day and 12:00 PM as midday.
Ignoring midnight. Subtracting a later start from an earlier end produces a negative interval. Add 24 hours to the end and recalculate.
Borrowing wrongly. Minutes borrow 60 from the hour column, not 10. Writing 12:97 instead of 11:117 is the classic slip.
Wrong dates in long mode. A mistaken month changes the answer by up to 31 days, and a mistaken year by 365 or 366.
Forgetting daylight saving. Spans that cross a transition are an hour off unless both endpoints are in the same fixed zone.
Rounding before subtracting. Round each interval at the end, not the inputs, or the errors accumulate across a pay period.
The words are often used interchangeably, but they point in different directions. Duration is the length you planned or expected; elapsed time is what actually passed.
A meeting scheduled for 2:00 to 3:00 PM has a planned duration of one hour. If it ran to 3:20, the elapsed time was 80 minutes and the overrun was 20. Tracking both is what makes estimates improve: after a few weeks of comparing the two, the gap between them becomes predictable and can be budgeted for.
The calculator serves either use. Enter scheduled times for the plan, actual times for the reality, and compare. For elapsed time measured in years and months, the Age Calculator does the calendar version.
Time estimates are usually wrong in a consistent direction, which makes them correctable. Recording actual start and end times for a week or two shows where the pattern sits.
The useful comparison is planned against actual, task by task. If meetings routinely run 20% long, the fix is to schedule 50-minute slots rather than to resolve to be quicker. If a recurring task takes three hours when you budget one, the calendar is the thing that needs changing.
Time blocking works better once those numbers exist. Blocking by feel tends to reproduce the same optimistic assumptions; blocking by measured duration produces a day that can actually be completed.
The arithmetic is simple once the base-60 borrowing is clear, and the edge cases are few: midnight, AM/PM, time zones, and daylight saving. Every one of them is a labelling problem rather than a mathematical one.
Use the tool for anything repetitive or second-precise, and do a calculation by hand occasionally so you can tell when a result is implausible. Local computation means there is no upload and no waiting, so checking a number costs nothing.
For the official U.S. time standard, see time.gov, maintained by NIST and the U.S. Naval Observatory.
The calculator finds the difference between two times in hours, minutes, and seconds. If the end time is before the start time, it assumes the end time is on the next day. For the date version, it calculates the full difference between two date and time values including days, hours, minutes, and seconds.
If the end time is earlier than the start time, the calculator assumes the end time is on the following day. For example, from 10 PM to 2 AM would be calculated as 4 hours. This handles overnight shifts, late-night events, and any scenario where time crosses midnight.
Yes, use the Time Between Two Dates section to enter start and end dates with times. The calculator will compute the total days, hours, minutes, and seconds across all days. This is useful for calculating durations spanning several days, weeks, or months.
Enter the hour (1-12), minutes (0-59), and seconds (0-59) in the provided fields. Select AM or PM from the dropdown. You can also use the Now link to quickly set the current time. The calculator handles the conversion to 24-hour format internally.
Yes, the Time Duration Calculator is completely free to use with no limits or registration required. All calculations are performed instantly in your browser.
Yes, you can calculate the duration between your start and end work times, including overnight shifts. Use the time-only section for same-day work hours or the date section for tracking hours across multiple days and pay periods.
AM hours are the same in both formats (1 AM = 1:00, 12 AM = 0:00). For PM hours, add 12 to the number (1 PM = 13:00, 11 PM = 23:00). 12 PM is 12:00. The calculator performs this conversion automatically.
Time duration and elapsed time essentially refer to the same concept: the amount of time between two points. Both measure the interval from start to end. Duration is often used for planning while elapsed time is used for measuring actual time that has passed.
Yes, the calculator includes seconds in both the time duration and date duration sections. You can enter seconds for precise calculations, which is useful for scientific timing, sports timing, and programming applications.
Yes, the Time Between Two Dates section handles dates across different months and years. Simply select the start and end dates using the date picker, set the times, and the calculator will compute the total duration in days, hours, minutes, and seconds.
The Now feature automatically sets the time fields to the current system time. Click the Now link next to any start or end time field to populate it with your current local time. This is helpful for calculating duration from the present moment.
Absolutely. The Time Duration Calculator is excellent for project planning, event scheduling, and timeline management. Calculate the duration of tasks, meetings, events, or any time-based activity. The date-duration feature is especially useful for long-term project planning.