Add or subtract time in days, hours, minutes and seconds.
| Days | |
| Hours | |
| Minutes | |
| Seconds |
| Total Days | |
| Total Hours | |
| Total Minutes | |
| Total Seconds |
This Time Calculator allows you to add or subtract time in days, hours, minutes, and seconds. Unlike normal decimal calculations, time calculations require special handling due to fixed unit conversions, such as 60 seconds in a minute and 24 hours in a day.
| Unit | Definition |
|---|---|
| Millennium | 1,000 years |
| Century | 100 years |
| Decade | 10 years |
| Year (average) | 365.242 days |
| Month | 28–31 days |
| Week | 7 days |
| Day | 24 hours (86,400 seconds) |
| Hour | 60 minutes |
| Minute | 60 seconds |
| Second | Base unit of time |
Throughout history, philosophers and scientists have debated the true nature of time. Aristotle viewed time as a measurement of change, while later thinkers questioned whether time exists independently or only in relation to events.
Isaac Newton believed time was absolute and flowed independently of the universe. Gottfried Leibniz argued that time only exists through relationships between events.
Albert Einstein later revolutionized this understanding with the theory of relativity, proving that time is relative and changes based on speed and gravity.
Modern timekeeping is based on the sexagesimal (base-60) system, originating from ancient civilizations. This system allows time units like hours and minutes to be easily divided.
Early timekeeping devices included sundials, water clocks, and hourglasses. Mechanical clocks later improved accuracy, and today atomic clocks provide the most precise time measurement available.
Because time uses fixed unit conversions such as 60 seconds per minute and 24 hours per day.
Yes, it can calculate time ranging from seconds to multiple days accurately.
Yes, it can be used for planning, education, work schedules, and personal calculations.
Yes, it follows standard time conversion rules used globally.
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