Time Conversion Formulas
Complete formulas for converting between different time units, from nanoseconds to centuries with detailed calculations.
â° Time Unit Hierarchy
Sub-Second
1 second = 1,000 milliseconds
1 second = 1,000,000 microseconds
1 second = 1,000,000,000 nanoseconds
Basic Units
1 minute = 60 seconds
1 hour = 60 minutes
1 hour = 3,600 seconds
Calendar Units
1 day = 24 hours
1 week = 7 days
1 month â 30.44 days
1 year = 365.25 days
Large Units
1 decade = 10 years
1 century = 100 years
1 millennium = 1,000 years
đ Basic Time Conversion Formulas
Seconds â Minutes â Hours
Seconds to Minutes
Example: 300 seconds
300 seconds = 5 minutes
Minutes to Hours
Example: 150 minutes
150 minutes = 2.5 hours
Seconds to Hours
Example: 7,200 seconds
7,200 seconds = 2 hours
Hours â Days â Weeks
Hours to Days
Example: 72 hours
72 hours = 3 days
Days to Weeks
Example: 21 days
21 days = 3 weeks
Hours to Weeks
Example: 336 hours
336 hours = 2 weeks
đ Calendar Time Conversions
Days â Months â Years
Days to Months (Average)
Example: 91 days
91 days â 3 months
Days to Years
Example: 1,826 days
1,826 days = 5 years
Leap Year Considerations
Regular Year
365 days
8,760 hours
525,600 minutes
31,536,000 seconds
Leap Year
366 days
8,784 hours
527,040 minutes
31,622,400 seconds
đ¯ Precise Conversion Factors
| From Unit | To Unit | Multiply By | Example |
|---|---|---|---|
| Milliseconds | Seconds | 0.001 | 5000 ms = 5 s |
| Seconds | Minutes | 0.01667 | 120 s = 2 min |
| Minutes | Hours | 0.01667 | 90 min = 1.5 hr |
| Hours | Days | 0.04167 | 48 hr = 2 days |
| Days | Weeks | 0.14286 | 14 days = 2 weeks |
| Days | Months | 0.03285 | 61 days â 2 months |
| Days | Years | 0.00274 | 730 days â 2 years |
𧎠Complex Time Calculations
Mixed Unit Conversions
Total Seconds in Mixed Time
Convert: 2 hours, 30 minutes, 45 seconds
Hours:
Minutes:
Seconds:
Total: 9,045 seconds
Seconds to Mixed Units
Convert: 10,000 seconds to h:m:s
Hours:
Remaining:
Minutes:
Seconds:
Result: 2:46:40
Time Zone & Geographic Calculations
Earth's Rotation
360° in 24 hours
Earth rotates 15° per hour
Solar vs Sidereal Day
Solar day: 24 hours (relative to sun)
Sidereal day: 23h 56m 4s (relative to stars)
Difference: 3 minutes 56 seconds
Sidereal day = 86,164 seconds
⥠Quick Reference Conversions
Small Units
1 minute60 seconds
1 hour3,600 seconds
1 day86,400 seconds
Medium Units
1 week7 days
1 monthâ30.44 days
1 quarterâ91.3 days
Large Units
1 year365.25 days
1 decade10 years
1 century100 years