Time · Duration Calculator
Time between two points
Set a start and an end. The answer updates as you type — no calculate button, no clutter.
Counted through midnight, into the next day.
This span crosses a daylight saving time change — the hour count reflects the actual clock shift, not a flat 24-hour day.
End is before start. Swap them, or check your dates.
How the calculation works
Both times are converted to seconds since midnight, then subtracted. If the end time is earlier than the start time, Between assumes the span crosses midnight and adds 24 hours automatically — so 22:00 to 03:00 correctly reads as 5 hours instead of throwing a negative number.
Example
08:15 → 16:45 = 8 hours 30 minutes
12-hour vs 24-hour time
Your browser's time input follows your system settings, so it may show a 12-hour clock with AM/PM or a 24-hour clock — either way, the calculation underneath is identical.
Two dates: daylight saving and leap years
The "Two dates" tab doesn't assume every day is 24 hours. It works out the real elapsed time between two exact moments, so if your span crosses a daylight saving change, the one day that's actually 23 or 25 hours long is counted correctly instead of silently losing or gaining an hour. Leap years are handled the same way — a range that includes February 29th counts that day like any other, and the calendar breakdown (years, months, days) is always based on real calendar lengths, not a fixed 30-day month.
Frequently asked questions
Does this handle overnight spans?
Yes. If your end time is earlier in the day than your start time, Between treats it as ending the next day and calculates accordingly. You can also tick "Ends next day" explicitly if a span happens to start and end at the same clock time 24 hours apart.
Does it include seconds?
The main input works in hours and minutes, matching how most people think about a schedule. The result panel shows the total down to the second.
Can I share a calculation with someone?
Yes — use "Copy shareable link." It saves your start and end time in the URL, so anyone who opens the link sees the same calculation.
Is my data stored anywhere?
No. Everything happens in your browser. Nothing is sent to a server or saved.
Does the "Two dates" calculator account for daylight saving time?
Yes. It compares two exact moments in your local time zone, so a span that crosses a spring-forward or fall-back change comes out as 23 or 25 hours for that one day rather than a flat 24 — you'll see a note when this happens.
Does it handle leap years correctly?
Yes. February 29th is counted like any other day, and the year/month/day breakdown always uses the real number of days in each month and year, so results stay accurate across leap years.
Related tools
More calculators in this family are on the way: hours between two dates, days between two dates, age in days, and time-until countdowns — all built on the same simple, fast interface.