Time Difference Calculator
Calculate the exact difference between two date-times, broken down into days, hours, minutes, and seconds.
Duration
- Total days
- 0.1250
- Total hours
- 3
- Total minutes
- 180
- Total seconds
- 10,800
How to use
- Set the From and To date-times — Now fills the current moment.
- Read the breakdown (D / H / M / S) and the total in each unit.
- If To is before From, the duration shows a reverse badge.
- Swap flips From and To.
About this tool
ShowHide
Pick two date-times and see the gap between them, split into days, hours, minutes, and seconds, with the total also expressed in each unit on its own. The difference is measured between the two instants themselves, not between calendar squares, which is the distinction that matters twice a year: a span that crosses a spring-forward reads as twenty-three hours rather than a full day, and a fall-back span reads as twenty-five, because that is genuinely how much time passed. Both fields use your device's local timezone, and Now fills in the current moment. If the end is earlier than the start, the duration is shown as a positive length with a reverse badge instead of a confusing negative number.
Frequently asked questions
What timezone is used?
Your device's local timezone. If you need to span timezones, convert both ends with the Timezone Converter first.
What does the reverse badge mean?
The 'To' date is earlier than 'From'. The duration is shown as a positive number, but reverse signals that you may want to swap them.
How precise is it?
Down to the second. Sub-second precision isn't exposed because the datetime-local input doesn't capture it.
Why is 'total days' fractional?
Days are shown to four decimal places so you can read durations like '2.5 days' precisely.
A range that crosses a daylight-saving change reads as 23 hours. Is that a bug?
No — that is how much time actually passed. The difference is measured between the two instants, not between calendar squares, so a spring-forward day is genuinely 23 hours long and an autumn day 25. A tool that reported 24 would be the one hiding something.
Why does the breakdown not include months?
Because a month has no fixed length, so days-hours-minutes-seconds is the largest set of units that stays exact. If you want a calendar answer — how many months and days lie between two dates — that is a different question, and the D-day calculator answers it.
Related tools
D-Day Calculator
Count the days between two dates, or the countdown to a target date.
Time
Duration Calculator
Add and subtract time durations in hours, minutes and seconds — get the total as h:m:s plus decimal hours, total minutes and total seconds.
Time
Add Business Hours to a Date
Add N working hours to a start datetime — skip weekends and holidays, respect a per-day work window, get the landing timestamp and a per-day breakdown.
Time
Moonrise, Moonset & Moon Position
Moonrise, moonset and transit times for any place and date, plus the Moon's altitude, azimuth, distance and illuminated fraction at a chosen moment.
Time
Date Calculator
Add or subtract years, months, weeks, days, and business days from any date — or find the difference between two dates.
Time
Slope & Line Calculator
From two points, get the slope, the line equation y = mx + b, the distance, midpoint, angle of inclination, and rise/run.
Math & Statistics