How many millisecond in 1 day?
The answer is 86400000.

We assume you are converting between **millisecond** and **day**.

You can view more details on each measurement unit:

millisecond or
day

The SI base unit for **time** is the second.

1 second is equal to 1000 millisecond, or 1.1574074074074E-5 day.

Note that rounding errors may occur, so always check the results.

Use this page to learn how to convert between milliseconds and days.

Type in your own numbers in the form to convert the units!

You may also want to find out how many days
are between two dates on the calendar. Use the
**date calculator**
to get your age in days or measure the duration of an event.

You can do the reverse unit conversion from day to millisecond, or enter any two units below:

The SI prefix "milli" represents a factor of
10^{-3}, or in exponential notation, 1E-3.

So 1 millisecond = 10^{-3} arcseconds.

The definition of a second is as follows:

A second of arc or arcsecond is a unit of angular measurement which comprises one-sixtieth of an arcminute, or 1/3600 of a degree of arc or 1/1296000 (approximately 7.7×10-7) of a circle. It is the angular diameter of an object of 1 unit diameter at a distance of 360×60×60/(2pi) (approximately 206,265 units), such as (approximately) 1 cm at 2.1 km, or, directly from the definition, 1 astronomical unit at 1 parsec.

A continous period of 24 hours which, unless the context otherwise requires, runs from midnight to midnight.

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