Hours Calculator
Use the calculators below to find the number of hours and minutes between two times. For a full time card, please use the Time Card Calculator.
Hours Between Two Dates
Instantly find the total hours, days, and minutes between any two dates and times. Perfect for calculating work durations, event intervals, or project timelines with precision and ease.
Understanding Hours & Time Formats
An hour is most commonly defined as a period of time equal to 60 minutes, where a minute is equal to 60 seconds, and a second has a rigorous scientific definition. There are also 24 hours in a day. Most people read time using either a 12-hour clock or a 24-hour clock.
12-hour clock:
A 12-hour clock uses the numbers 1–12. Depending on the clock being used, most analog clocks or watches may not include an indication of whether the time is in the morning or evening. On digital clocks and watches, "AM" stands for ante meridiem, meaning "before midday," while "PM" stands for post meridiem, or "after noon." By convention, 12 AM denotes midnight, while 12 PM denotes noon.
24-hour clock:
A 24-hour clock typically uses the numbers 0–23, where 00:00 indicates midnight, and a day runs from midnight to midnight over the course of 24 hours. This format avoids the ambiguity of AM/PM and is widely used internationally and in military contexts.