mm to µm Converter
Type a value in millimeters to see it in micrometers as you type, with the exact formula and a reference chart.
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How this was calculated
- 1 millimeter = 1,000 micrometers
- 1 × 1,000 = 1,000 µm
| mm | µm |
|---|---|
| 0.001 mm | 1 µm |
| 0.01 mm | 10 µm |
| 0.05 mm | 50 µm |
| 0.1 mm | 100 µm |
| 0.25 mm | 250 µm |
| 0.5 mm | 500 µm |
| 1 mm | 1,000 µm |
| 2 mm | 2,000 µm |
| 5 mm | 5,000 µm |
| 10 mm | 10,000 µm |
| 25 mm | 25,000 µm |
| 50 mm | 50,000 µm |
| 100 mm | 100,000 µm |
| µm | mm |
|---|---|
| 1 µm | 0.001 mm |
| 2 µm | 0.002 mm |
| 5 µm | 0.005 mm |
| 10 µm | 0.01 mm |
| 20 µm | 0.02 mm |
| 50 µm | 0.05 mm |
| 100 µm | 0.1 mm |
| 200 µm | 0.2 mm |
| 500 µm | 0.5 mm |
| 1,000 µm | 1 mm |
| 2,000 µm | 2 mm |
| 5,000 µm | 5 mm |
How to convert millimeters to micrometers
1 millimeter = 1,000 micrometers. To convert millimeters to micrometers, multiply by 1,000. A millimeter is one thousandth of a meter. A micrometer (µm, also called a micron) is one millionth of a meter, one thousandth of a millimeter.
Worked examples
- 0.1 millimeters = 100 µm (0.1 × 1,000)
- 1 millimeter = 1,000 µm (1 × 1,000)
- 2.5 millimeters = 2,500 µm (2.5 × 1,000)
Where this conversion comes up
Millimeters are used for screw and drill sizes, rainfall, paper and phone dimensions; micrometers for dust and pollen particles, filter ratings, bacteria and coating thickness. Machining tolerances, coating thickness and filter ratings switch between millimeters and micrometers (microns). One millimeter is exactly 1,000 µm, so a 0.05 mm tolerance is 50 µm. A human hair is roughly 50 to 100 µm wide.
Quick estimate
Multiply by 1,000: 0.2 mm = 200 µm.
Common mistakes
- Dividing instead of multiplying. A micrometer is smaller than a millimeter, so the number of micrometers must come out larger: 0.1 millimeters = 100 µm.
Related length converters: mm to inches, inches to mm, inches to feet, feet to inches, meters to feet, feet to meters.
Frequently asked questions
How do you convert millimeters to micrometers?
Multiply the millimeters by 1,000. For example, 1 millimeter is 1,000 micrometers.
How many micrometers are in one millimeter?
One millimeter is 1,000 micrometers. A millimeter is one thousandth of a meter.
What is 2.5 millimeters in micrometers?
2.5 millimeters is 2,500 micrometers.
Is there a quick way to estimate millimeters to micrometers?
Multiply by 1,000: 0.2 mm = 200 µm.