Microseconds to Milliseconds (µs to ms)

1 microsecond equals 0.001 milliseconds exactly.

1 microsecond = 0.001 milliseconds

How to convert microseconds to milliseconds

To convert microseconds to milliseconds, multiply the number of microseconds by 0.001. This factor is exact. To go the other way, multiply milliseconds by 1,000.

milliseconds = microseconds × 0.001

Example: 10 microseconds = 0.01 milliseconds.

Months and years are not constant. This site uses the average Gregorian year of 365.2425 days, so one 'year' converts to 365.2425 days, not 365; use 'common year' for exactly 365 days.

About these units

Microsecond (µs)

Metric (SI)Current unit

One millionth of a second. Used for electronics and processor timing.

Writing a microsecond takes a Greek letter, mu, which stands for the prefix micro-, one millionth. Where plain text cannot display it, people fall back on the letter u and write us. The unit belongs to electronics and radio: a signal that repeats every microsecond has a frequency of 1 MHz, and a radio wave of that period is about 300 m long.

A microsecond is one millionth of a second, short enough that light in a vacuum crosses only about 1 km in 3.34 of them. Digital audio lives on this scale, because a CD sample at 44.1 kHz lasts about 22.7 microseconds and a 48 kHz sample about 20.8. A modern solid-state drive has an access latency of about 50 microseconds, and a camera flash lasts around 1,000. Relativity matters at this scale too: GPS satellite clocks would drift by about 38 microseconds per day without compensation. Wikipedia notes that the 2011 Japanese earthquake shortened the day by about 1.8 microseconds.

1 microsecond = 0.000001 seconds (exactly).

Sources: Wikipedia: Microsecond; BIPM: SI Brochure, 9th edition

Millisecond (ms)

Metric (SI)Current unit

One thousandth of a second. Used for computer response times and sports timing.

Milliseconds sit on the border between what people perceive and what instruments must be built to catch. Nobody feels a single one: a human blink lasts roughly 100 to 400 of them, and the average resting heart cycle is about 860. The prefix milli- makes the unit exactly one thousandth of a second, so it is a handy yardstick for events a little too quick to notice but slow enough for a stopwatch-style instrument to capture.

A millisecond is one thousandth of a second, and the scale references are easy to picture. Light in a vacuum covers about 300 km in 1 ms, and sound in air covers about 34 cm. A film frame at 24 frames per second lasts about 41.7 ms, one cycle of 60 Hz mains power lasts about 16.7 ms, and a camera shutter set to 1/125 s is open for about 8 ms. Online gamers watch network latency in milliseconds, with typical broadband figures of 5 to 80 ms, and telephone engineers recommend keeping one-way delay under about 150 ms before conversation starts to feel awkward.

1 millisecond = 0.001 seconds (exactly).

Sources: Wikipedia: Millisecond; BIPM: SI Brochure, 9th edition

Related conversions

See all time units.