The micrometer (micron)
The micrometer (µm), also called the micron, equals one-millionth of a meter. It is the working unit for semiconductor feature sizes, human hair and cell diameters, and precision-manufacturing tolerances.
Micrometers to Millimeters Converter
1 µm = 0.001 mm (micrometer (micron) → millimeter)
1 µm = 0.001 mm
1 micrometer (micron) equals 0.001 millimeters. To convert micrometers to millimeters, multiply the micrometer (micron) value by 0.001. For quick reference: 1 µm = 0.001 mm, 5 µm = 0.005 mm, 10 µm = 0.01 mm, 100 µm = 0.1 mm.
Formula
Millimeters = Micrometers × 0.001Quick
How to convert micrometers to millimeters
Take your value
Start with your value in micrometers.
Multiply by 0.001
Multiply the micrometer (micron) value by 0.001. This is the exact conversion factor from micrometers to millimeters.
Read the result
The product is your value in millimeters. For example, 5 µm × 0.001 = 0.005 mm.
Conversion formula
The exact factor from micrometers to millimeters is 0.001.
Millimeters = Micrometers × 0.001
Micrometers to Millimeters conversion table
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Micrometers (µm) | Millimeters (mm) |
|---|---|
| 0.1 µm | 1.0000 × 10^−4 mm |
| 0.25 µm | 0.00025 mm |
| 0.5 µm | 0.0005 mm |
| 1 µm | 0.001 mm |
| 2 µm | 0.002 mm |
| 3 µm | 0.003 mm |
| 4 µm | 0.004 mm |
| 5 µm | 0.005 mm |
| 6 µm | 0.006 mm |
| 7 µm | 0.007 mm |
| 8 µm | 0.008 mm |
| 9 µm | 0.009 mm |
| 10 µm | 0.01 mm |
| 11 µm | 0.011 mm |
| 12 µm | 0.012 mm |
| 13 µm | 0.013 mm |
| 14 µm | 0.014 mm |
| 15 µm | 0.015 mm |
| 16 µm | 0.016 mm |
| 18 µm | 0.018 mm |
| 20 µm | 0.02 mm |
| 22 µm | 0.022 mm |
| 24 µm | 0.024 mm |
| 25 µm | 0.025 mm |
| 28 µm | 0.028 mm |
| 30 µm | 0.03 mm |
| 32 µm | 0.032 mm |
| 36 µm | 0.036 mm |
| 40 µm | 0.04 mm |
| 45 µm | 0.045 mm |
| 48 µm | 0.048 mm |
| 50 µm | 0.05 mm |
| 60 µm | 0.06 mm |
| 70 µm | 0.07 mm |
| 75 µm | 0.075 mm |
| 80 µm | 0.08 mm |
| 90 µm | 0.09 mm |
| 100 µm | 0.1 mm |
| 125 µm | 0.125 mm |
| 150 µm | 0.15 mm |
| 200 µm | 0.2 mm |
| 250 µm | 0.25 mm |
| 300 µm | 0.3 mm |
| 400 µm | 0.4 mm |
| 500 µm | 0.5 mm |
| 600 µm | 0.6 mm |
| 750 µm | 0.75 mm |
| 800 µm | 0.8 mm |
| 900 µm | 0.9 mm |
| 1000 µm | 1 mm |
Real-world reference
A human hair is about 70 µm in diameter. A red blood cell is roughly 7–8 µm across.
Frequently asked questions
- How many millimeters are in 1 micrometer (micron)?
- 1 micrometer (micron) equals 0.001 millimeters.
- How do I convert micrometers to millimeters?
- Multiply the micrometer (micron) value by 0.001. So x µm × 0.001 = the equivalent in mm.
- What is 5 micrometers in millimeters?
- 5 micrometers equals 0.005 millimeters.
- What is 10 micrometers in millimeters?
- 10 micrometers equals 0.01 millimeters.
- What is 100 micrometers in millimeters?
- 100 micrometers equals 0.1 millimeters.
- How do I convert back from millimeters to micrometers?
- Multiply the millimeter value by 1000. For example, 1 mm = 1000 µm.
- Is the micrometer (micron) bigger than the millimeter?
- No. 1 micrometer (micron) is smaller than 1 millimeter. It takes 1000 micrometers to equal 1 millimeter.
- Are these conversion factors exact?
- The factor is derived directly from the SI definitions of micrometer (micron) and millimeter; the displayed value is rounded for readability, and the browser computes using IEEE 754 double-precision arithmetic.
About the micrometer (micron) and the millimeter
The millimeter
The millimeter (mm) is a metric unit of length equal to one-thousandth of a meter. It is the working unit of engineering drawings, precision manufacturing, electronics, and most consumer-goods specifications outside the United States. A credit card is about 0.76 mm thick; the diameter of a pencil lead is around 2 mm.