Convert micrometers to millimeters

1 µm = 0.001 mm. Change the amount below, or read the formula and the reference table further down.

1 micrometer equals

0.001millimeters

1 µm = 0.001 mm

The formula

Micrometers and millimeters both measure length from the same zero, so a single multiplier does the job.

mm = µm × 0.001

Going the other way? Convert millimeters to micrometers.

Micrometers to millimeters table

Common values, rounded for reading.

Micrometers (µm)Millimeters (mm)
10.001
20.002
30.003
40.004
50.005
60.006
70.007
80.008
90.009
100.01
150.015
200.02
250.025
300.03
400.04
500.05
750.075
1000.1
2500.25
5000.5
1,0001

Questions people ask

How many millimeters are in a micrometer?
One micrometer equals 0.001 millimeters.
How do I convert micrometers to millimeters by hand?
Multiply the number of micrometers by 0.001. For a rough check, 0.001 is close enough for most everyday use.
What is 1 micrometer in millimeters?
1 micrometer is 0.001 millimeters.

Calcuit generates this page from a unit table, so the factors here match every other page on the site.

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