d

What is a Day?

Time Unit

Definition

A day is a unit of time equal to 24 hours or 86,400 seconds, representing one rotation of Earth on its axis.

Popular Day Conversions

Most common conversions from Days

1 d = 86,400 s Day to Seconds 1 d = 86,400,000 ms Day to Milliseconds 1 d = 86,400,000,000 μs Day to Microseconds 1 d = 86,400,000,000,000 ns Day to Nanoseconds 1 d = 1,440 min Day to Minutes 1 d = 24 h Day to Hours

History

The day is one of the oldest units of time, based on the cycle of light and darkness. The 24-hour day comes from ancient Egypt.

Common Uses

Calendar dates
Work schedules
Medication dosing
Travel planning

Fun Facts

💡

A day on Mars is about 24 hours and 37 minutes

💡

A day on Venus is longer than its year

💡

The Earth's day is gradually getting longer

All Day Conversions

Days to Seconds d → s Days to Milliseconds d → ms Days to Microseconds d → μs Days to Nanoseconds d → ns Days to Minutes d → min Days to Hours d → h Days to Weeks d → wk Days to Months d → mo Days to Years d → yr