Micrometers to Meters Converter

Common questions

How many meters is 1 micrometer?

0.000001 m, one millionth of a metre, because a million micrometres make a metre. The pattern holds at every size: 5 µm is 0.000005 m, 70 µm is 0.00007 m, 250 µm is 0.00025 m, 1,500 µm is 0.0015 m, 12,345 µm is 0.012345 m and 1,000,000 µm is 1 m. The conversion moves the decimal point six places to the left, and the displayed result rounds longer inputs to twelve significant digits.

What is the formula for micrometers to meters?

Metres = micrometres / 1,000,000, and micrometres = metres × 1,000,000 in the other direction, so 0.004 m is 4,000 µm. The metre has been fixed since 1983 by defining the speed of light as 299,792,458 metres per second, and micro means one millionth, so the micrometre is one millionth of that metre by definition. The Swap units button between the two boxes reverses the pair, so this page turns into a metres to micrometres converter without a reload.

How do micrometers, millimeters and nanometers relate?

Each step is a factor of 1,000: 1 mm is 1,000 µm and 1 µm is 1,000 nm, so a metre is 1,000 mm, 1,000,000 µm and 1,000,000,000 nm. That is where the common slip lives, since writing 100 mm when you meant 100 µm is a thousandfold error. One thou, the imperial neighbour also written mil, is 25.4 µm exactly. Nanometre and thou are uncommon units here: both dropdowns always list them, and the Uncommon units switch in the readout, labelled Show 7 more, is what adds them to the list under the answer, along with furlong, astronomical unit, light year and parsec. Micrometre is not repeated there, because it is the unit you are converting from.

Where are micrometers actually used?

Machining tolerances and surface finish, coating and film thickness, filter ratings, 3D printer layer heights, particulate sizes and optical wavelengths all sit in this range, which is why the numbers that come out are small in metres. PM2.5 particles are 2.5 µm, or 0.0000025 m. Visible light runs roughly 0.38 to 0.75 µm, so 0.38 µm reads 3.8e-7 m in exponential notation. A red blood cell is about 7.5 µm, or 0.0000075 m.

Is the decimal exact, or is it rounded?

The relation is exact and the decimal is short, because a million is a power of ten: converting only shifts the decimal point, so there is no repeating tail of the kind you get converting to inches, where 1 µm is 0.0000393700787402 in at twelve significant digits. Displayed answers round at those twelve digits, well inside what the arithmetic carries, and a magnitude below 0.000001 is printed in exponential notation instead: 0.5 µm reads 5e-7 m and 0.1 µm reads 1e-7 m.

Is a micron the same as a micrometer?

Yes. Micron is the older name for the same unit, one millionth of a metre, so a 5 micron filter rating and a 5 µm rating are the same number and both are 0.000005 m. SI dropped the name in 1967 and kept the unit, which is why filtration, coatings and 3D printing still say microns while the symbol on a drawing is µm. In the From box here the unit is listed as Micrometre (µm); the arithmetic is identical whichever word you came for.

What does the list under the answer show?

The same length in every common length unit at once, rather than one target at a time. Type 250 in the From box and the headline reads 0.00025 m, with 0.25 mm, 0.025 cm, 2.5e-7 km, 0.00984251968504 in, 0.000820209973753 ft and 0.000273403324584 yd in the list below. The box accepts a typed exponent as well, so 2.5e6 is read as 2,500,000 µm. Copy result copies the headline exactly as printed, without the thousands separators.

Why does the page open on µm and m when I last converted something else?

Because a page that names a pair should show that pair. This one sets micrometres and metres on arrival, ahead of whatever the converter last remembered, and it leaves the main unit converter's own memory alone: go back there and it is still on the pair you left it on. The number you last typed does come with you, since it is usually the one you are still working on.