Nm to Micrometers Converter

Common questions

How many micrometers is 1 nanometer?

0.001 µm, because one thousand nanometres make a micrometre. The pattern holds at every size: 25 nm is 0.025 µm, 70 nm is 0.07 µm, 100 nm is 0.1 µm, 400 nm is 0.4 µm, 700 nm is 0.7 µm and 1,000 nm is exactly 1 µm. Going up from there only moves the point further: 1,000,000 nm is 1,000 µm. The displayed result rounds longer inputs to twelve significant digits.

What is the formula for nm to µm?

Micrometres = nanometres / 1,000, and nanometres = micrometres × 1,000 the other way, so 0.25 µm is 250 nm. Both units come from the metre by SI prefix, nano for 10 to the minus 9 and micro for 10 to the minus 6, which leaves exactly three orders of magnitude between them. Because the factor is a power of ten, the conversion only shifts the decimal point and there is no repeating tail of the kind you get converting to inches, where 1,000 nm is 0.0000393700787402 in.

How do I read an optical wavelength in microns?

Divide the nanometre figure by 1,000. Visible light runs roughly 380 to 700 nm, which is 0.38 to 0.7 µm, the range spectroscopy and optics papers usually write in microns. A 1,064 nm Nd:YAG line is 1.064 µm and a 1,550 nm telecom line is 1.55 µm, so anything past about 750 nm is over the 0.75 µm mark and into the near infrared. Type the nanometre number in the From box and the headline is the micron figure.

Is a 7 nm chip 0.007 micrometres wide?

Arithmetically yes: 7 nm is 0.007 µm and 5 nm is 0.005 µm. Physically the node name has not matched any single measured dimension on the die for years; it is a process generation label, not a width you can convert into a feature size. The conversion here is honest about the numbers and says nothing about what the numbers describe: if you need a real dimension, take it from the datasheet rather than from the node name.

Where is micrometre in the list under the answer?

Behind the uncommon units switch. Nanometre and micrometre are both filed as uncommon in the length category, so by default the list under the headline shows millimetres, centimetres, metres, kilometres, inches, feet, yards, miles and nautical miles, and the µm figure is the headline itself. Flip the switch in the readout, labelled Show 7 more, and the list adds micrometre, thou, furlong, astronomical unit, light year and parsec. Nanometre never appears there, because it is the unit you are converting from. Both dropdowns list every length unit at all times, uncommon ones included.

Can I convert micrometers back to nanometers here?

Yes. The Swap units button between the two boxes reverses the pair, so this page becomes a micrometres to nanometres converter without a reload: 0.25 µm gives 250 nm and 1.55 µm gives 1,550 nm. Both unit menus stay open as well, so the same number will go from nanometres to millimetres, metres or inches without leaving the page.

Is a micron the same as a micrometer, and what was a millimicron?

A micron is a micrometre: the older name for one millionth of a metre, dropped by SI in 1967 while the unit stayed, which is why coatings, filtration and machining still talk in microns. A millimicron was the old name for what is now the nanometre, a thousandth of a micron, so an old paper quoting 550 millimicrons means 550 nm, which is 0.55 µm. In the From box here the units are listed as Nanometre (nm) and Micrometre (µm); the arithmetic is the same whichever word you came for.

What about ångströms, and where does thou fit?

The length list here does not carry the ångström, so convert it by hand first: 1 Å is 0.1 nm, which makes 10 Å one nanometre and 3.5 Å, a typical atomic spacing, 0.00035 µm. Thou is in the list, behind the uncommon units switch: one thou, also written mil, is 25,400 nm or 25.4 µm exactly, so 1,000 nm is 0.0393700787402 thou. Surface finish is the place these meet, since an Ra of 0.4 µm is the same as 400 nm.

Why does a result sometimes read 5e-7 instead of a decimal?

Because a magnitude below 0.000001 is printed in exponential notation, which beats counting zeroes. With 500 in the From box the headline is 0.5 µm and the list under it reads 0.0005 mm, 0.00005 cm, 5e-7 m and 5e-10 km, with 0.0000196850393701 in and 5.468066e-7 yd. The value box reads exponents too, so typing 2.5e3 is taken as 2,500 nm. Copy result copies the headline exactly as printed, without the thousands separators, so 1,000,000 nm copies as 1000.

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

Because a page that names a pair should show that pair. This one sets nanometres and micrometres 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.