Time Conversion Calculator
Enter the time value and units you want to convert from, then choose the time unit you want to convert to. You can convert between seconds, milliseconds, microseconds, nanoseconds, days, hours, weeks, months, and years.
Note about time units:
Months in this time conversion calculator are calculated using the average of 30.416 days per month. This is equal to 365 days per year divided by 12 months per year. Years in this time converter are calculated as 365 days per year. This calculator does not consider the extra day in a leap year which has 366 days per year.
| Time Unit | Value | Symbol |
|---|---|---|
| Nanoseconds | - | ns |
| Microseconds | - | µs |
| Milliseconds | - | ms |
| Seconds | - | s |
| Minutes | - | min |
| Hours | - | h |
| Days | - | d |
| Weeks | - | wk |
| Months | - | mo |
| Years | - | yr |
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Time Conversion Calculator
Accurately converting between different units of time is essential in science, engineering, computing, and everyday life. The Time Conversion Calculator simplifies this process, letting you instantly convert between seconds, milliseconds, microseconds, nanoseconds, minutes, hours, days, weeks, months, and years.
What Is a Time Conversion Calculator?
A Time Conversion Calculator is a digital tool that allows users to switch between various units of time with precision. Whether you’re adjusting a project timeline, synchronizing system clocks, or analyzing astronomical data, this calculator saves time and prevents conversion errors.
Months in this calculator are calculated using the average of 30.416 days per month (365 ÷ 12), while years are calculated as 365 days. Leap years with 366 days are excluded for simplicity and consistency.
How to Convert Units of Time
Converting between units of time involves using conversion factors — numerical values that define how one unit relates to another.
The general conversion formula is:
S × C = E
Where:
- S = starting value
- C = conversion factor
- E = converted result
For example:
- To convert 120 minutes to seconds, multiply 120 by 60:
120 × 60 = 7,200 seconds - To convert 28,800 seconds to hours, divide by 3,600:
28,800 ÷ 3,600 = 8 hours
This calculator automates these steps, giving you accurate results instantly.
Common Time Conversion Factors
Below are the most widely used conversion factors to transform any time unit into seconds:
| From Unit | Symbol | Multiply by (Seconds per Unit) |
|---|---|---|
| Nanosecond | ns | 0.000000001 |
| Microsecond | μs | 0.000001 |
| Millisecond | ms | 0.001 |
| Second | s | 1 |
| Minute | min | 60 |
| Hour | h | 3,600 |
| Day | d | 86,400 |
| Week | wk | 604,800 |
| Month | mo | 2,628,000 |
| Year | yr | 31,536,000 |
| Decade | dec | 315,360,000 |
| Century | c | 3,153,600,000 |
| Millennium | — | 31,536,000,000 |
To convert from one unit to another, multiply by the factor to convert to seconds, then divide by the factor for the desired unit.
For example:
To convert minutes to hours, multiply by 60 (to get seconds) and divide by 3,600:
minutes × 60 ÷ 3,600 = hours
Simplified, that’s minutes × 0.0167 = hours.
Understanding Sidereal Time
Astronomers often use sidereal time, which measures Earth’s rotation relative to distant stars rather than the sun.
A sidereal day equals 23 hours, 56 minutes, and 4.09 seconds, or 86,164.09 seconds — slightly shorter than a solar day.
This difference matters in astronomy and satellite tracking, where even a few seconds can affect calculations.
Practical Applications of Time Conversion
Time conversion is used across various industries and scenarios:
- Computing – Converting milliseconds or microseconds for algorithm performance measurement.
- Engineering – Synchronizing processes or event logs across systems.
- Astronomy – Measuring sidereal periods or celestial object rotations.
- Education – Teaching units and dimensional analysis.
- Everyday Use – Converting weeks into months or days for project planning.
If you’re dealing with calculations involving distance, try the distance conversion tool to convert miles, meters, and kilometers with equal ease.
Converting Larger and Smaller Time Units
Some time units represent incredibly small intervals, like nanoseconds (1 billionth of a second), while others span long durations such as centuries or millennia.
Example Calculations:
- Convert 2.5 days to seconds:
2.5 × 86,400 = 216,000 seconds - Convert 10 years to hours:
10 × 8,760 = 87,600 hours - Convert 5,000 milliseconds to seconds:
5,000 × 0.001 = 5 seconds
The calculator’s precision ensures these conversions remain accurate even across extreme ranges.
Conversion Formula Simplified
You can easily perform manual conversions using this plain-text formula:
New Value = Original Value × (Factor of Original Unit / Factor of Desired Unit)
Example: Convert 2 hours into minutes:
2 × (3,600 ÷ 60) = 120 minutes
Why Use an Online Time Conversion Calculator?
Manual conversion can be error-prone, especially when dealing with fractions or complex units. An online calculator offers:
- Instant results – No need to memorize factors.
- Error-free conversions – Automatic calculations reduce mistakes.
- Comprehensive coverage – Includes rare and sidereal time units.
- Educational clarity – Demonstrates formulas and relationships clearly.
For related functionality, explore the metric units converter for converting between various measurement systems.
Related Time Conversions
If you frequently work with time-based calculations, these conversions may also help:
- Minutes to Hours Converter – Quickly switch between minute and hour formats.
- Minutes to Decimal Converter – Useful for payroll and data entry accuracy.
These specialized tools complement the Time Conversion Calculator by providing quick access to specific time formats and decimal conversions.
Key Takeaways
- 1 hour = 3,600 seconds
- 1 day = 24 hours = 86,400 seconds
- 1 year = 365 days = 31,536,000 seconds
- Formula: S × C = E
- Months average 30.416 days for conversion purposes
The Time Conversion Calculator is an indispensable tool for anyone who regularly works with time units — from students and teachers to engineers and astronomers. With accurate conversion factors and an easy-to-use interface, it transforms what used to be tedious manual work into a quick, reliable process.
Accurate time conversion isn’t just about numbers; it’s about synchronizing knowledge across disciplines, bridging the nanosecond with the millennium — all in one seamless calculation.
References/ Further Reading
The National Institute of Standards and Technology (NIST) – The NIST Guide for the Use of the International System of Units – Appendix B, subsections B.8 Factors for Units Listed Alphabetically and B.9 Factors for units listed by kind of quantity or field of science.
Lide, David R., Daniel (Editor-in-Chief). CRC Handbook of Chemistry and Physics, 89th Edition, New York, NY: CRC Press, p. 1-28, 2008.
Wikipedia contributors. “Conversion of units” Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, last visited 26 Jun. 2011.