Time Calculator & Unit Converter
From milliseconds to centuries. Perform atomic-level precision conversions and explore the science behind how we measure the fourth dimension.
Convert Time
Quick Conversions
Results
Enter time value and select units to convert
Time Scale
Common Time Periods
Time Conversion Factors
Minute to Second
1 min = 60 s
Hour to Minute
1 hr = 60 min
Day to Hour
1 d = 24 hr
Week to Day
1 wk = 7 d
How to Use This Time Converter
Enter Duration
Type the amount of time you want to convert.
Select Time Units
Pick your starting unit (e.g., Minutes) and target unit (e.g., Seconds).
See Result
The conversion appears instantly for you.
Why is Time So Math-Unfriendly?
Most of our metric world uses Base 10 (10mm = 1cm, 100cm = 1m). Time, however, is a rebellious relic of ancient history. We use the Sexagesimal System (Base 60) for short durations (60s = 1m, 60m = 1h) and a mix of solar and lunar cycles for long durations.
This system dates back to the ancient Sumerians (~3500 BC), who loved the number 60 because it is easily divisible by 1, 2, 3, 4, 5, and 6. While great for fraction partitioning without calculators, it makes mental math (like "how many minutes in 1.4 days?") a nightmare for modern humans.
Physics Corner: Time Dilation
Does Time Pass at the Same Speed for Everyone?
No! According to Einstein's Theory of Relativity, time is fluid. It slows down when you move fast or are near a heavy gravity source.
- Velocity Time Dilation: If you flew vertically at 99% the speed of light for 1 year, when you returned to Earth, decades or centuries would have passed for everyone else.
- Gravitational Time Dilation: Time passes slightly faster at the top of a skyscraper than at the bottom because gravity is weaker.
- Real World Impact: GPS satellites move fast and are in lower gravity. Their clocks drift by about 38 microseconds per day relative to Earth. If engineers didn't correct for this "Time Warp," your GPS would be off by miles within a day!
The Scale of Time
| Unit | Scientific Notation | Concept |
|---|---|---|
| Planck Time | 5.39 × 10⁻⁴⁴ s | The smallest possible unit of time in physics. |
| Microsecond | 10⁻⁶ s | High-speed camera shutter speed. |
| Second | 1 s | Base unit. Approx. one human heartbeat. |
| Galactic Year | ~230 million yrs | Time for the Solar System to orbit the Milky Way once. |
Common Questions
What is a Leap Second?
Earth's rotation is slowing down slightly due to tidal friction. Occasionally, the IERS adds one second to the world clock (UTC) to keep atomic time in sync with solar time.
Has "Decimal Time" ever been tried?
Yes! During the French Revolution (1793), France introduced Decimal Time: 10 hours in a day, 100 minutes in an hour, 100 seconds in a minute. It was confusing and hugely unpopular, surviving only a few years.
Is a Light Year a unit of time?
No! This is a common misconception. A Light Year is a unit of distance (the distance light travels in one year, ~5.88 trillion miles). Using it to measure time is like saying "I'll be there in 3 miles."