Millimeters to micrometers
Type a value in millimeters to see it in micrometers straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the millimeters box.
- Read the result in micrometers as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
µm = mm × 1,000
Multiply the value in millimeters by 1,000 to get micrometers.
Example
To convert 25 mm to micrometers: 25 × 1,000 = 25,000 µm.
Conversion table
| Millimeters (mm) | Micrometers (µm) |
|---|---|
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 100 | 100,000 |
| 250 | 250,000 |
| 500 | 500,000 |
| 1,000 | 1,000,000 |
About the units
- Millimeter
- A millimeter is one thousandth of a meter, common in engineering drawings and thickness measurements.
- Micrometer
- A micrometer (micron) is one millionth of a meter, used for hair width, filters and coating thickness.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many micrometers are in one millimeter?
1 mm = 1,000 µm exactly.
How do I convert millimeters to micrometers?
Use µm = mm × 1,000. For example, 25 mm = 25,000 µm.
How many millimeters are in one micrometer?
1 µm = 0.001 mm.
Are the inch, foot and mile factors exact or rounded?
They are exact by definition. Since the 1959 agreement one inch is exactly 2.54 cm, one foot 0.3048 m and one mile 1609.344 m.
What is the difference between a mile and a nautical mile?
A statute mile is 1609.344 meters and is used on roads. A nautical mile is 1852 meters and is used at sea and in aviation.