Convert second to day
Enter the value to convert from second to day.
How to Convert Second to Day
Converting second to day is straightforward using our conversion calculator.
Conversion Formula
d = s ÷ 86400Reverse conversion: Convert day to second
Comparison: Second vs Day
When to Use Each Unit
Second: Universal time unit for scientific measurements, computing, engineering, and precise timing applications worldwide.
Day: Fundamental unit for calendars, scheduling, biological rhythms, and organizing human activities globally.
Common Conversion Values
- 60 s = 1 min
- 3,600 s = 1 h
- 86,400 s = 1 day
- 1 s = 1000 ms
About Second
Definition: The second (symbol: s) is the SI base unit of time, defined as the duration of 9,192,631,770 periods of radiation from cesium-133 atoms.
History: Originally defined as 1/86400 of a mean solar day. Redefined in 1967 using atomic transitions for unprecedented accuracy.
Current Use: Universal time unit for scientific measurements, computing, engineering, and precise timing applications worldwide.
Examples: Computer processing: microseconds, sports timing: hundredths of seconds, atomic clocks: nanosecond precision
About Day
Definition: The day (symbol: d) is a unit of time equal to 24 hours, based on Earth's rotation period.
History: Based on natural solar day cycle. Standardized to exactly 24 hours with development of mechanical timekeeping.
Current Use: Fundamental unit for calendars, scheduling, biological rhythms, and organizing human activities globally.
Examples: Project deadlines: 1-30 days, vacation: 3-14 days, medication: daily doses, rental periods: daily rates