Milliseconds to Microseconds Converter

What this converter does

This turns a number of milliseconds into microseconds. Both are small slices of a second, and a microsecond is the smaller of the two, so the number always grows when you make the switch. Enter the milliseconds and you get the microseconds straight back, handy when you are doing timing work and need the finer unit.

How to use it

1. Enter Milliseconds. Type the number of milliseconds.

Press Calculate and the equivalent in microseconds appears.

One step down the metric ladder

The small units of time stack in a neat ladder, each rung a thousand times finer than the one above: a second holds a thousand milliseconds, a millisecond holds a thousand microseconds, and a microsecond holds a thousand nanoseconds. Milliseconds to microseconds is a single step down that ladder, so the rule is simply to multiply by 1,000. One millisecond is 1,000 microseconds, ten milliseconds is 10,000, and so on. There is nothing approximate here, since these are exact relationships between the units.

Why drop to microseconds

You reach for microseconds when milliseconds are too coarse to show what you are looking at. Milliseconds are the scale of things people can almost feel, like a network round trip or a screen refresh, but a lot happens far quicker than that. Timing a fast function, comparing two code paths that both finish in under a millisecond, or profiling something where the differences hide below the millisecond mark all need the extra resolution. Switching to microseconds gives you three more digits of detail to work with.

An example

Say a measurement comes in at 5 milliseconds. Multiply by 1,000 and that is 5,000 microseconds. A smaller one: 0.25 milliseconds is 250 microseconds. The number gets bigger because you are now counting in smaller pieces, the same length of time measured with a finer ruler.

Questions people ask

How many microseconds are in a millisecond?

1,000. So to convert, you multiply the milliseconds by 1,000. Five milliseconds is 5,000 microseconds.

Why does the number get bigger?

Because a microsecond is smaller than a millisecond, so it takes more of them to fill the same span. Finer unit, larger count.

Is the conversion exact?

Yes. A millisecond is exactly 1,000 microseconds by definition, so there is no rounding or approximation involved.

How do I go back?

Divide the microseconds by 1,000, or use a microseconds-to-milliseconds converter, which does that step for you.

References

1. BIPM, The International System of Units (SI) Brochure, SI prefixes. https://www.bipm.org/en/publications/si-brochure