Convert Millimeters to Micrometers
1 millimeter (mm) equals 1000 micrometers (µm).
1 mm = 1000 µm
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk millimeter to micrometer converter to paste a column from Excel.
How to Convert Millimeter to Micrometer
- 1 mm = 1000 µm
- 1 µm = 0.001 mm
- Example: convert 15 mm to µm: 15 mm = 15 × 1000 µm = 15000 µm
Formula
µm = mm × 1000
Derivation from SI units:
- 1 mm = 10⁻³ m
- 1 µm = 10⁻⁶ m
- 1 mm = 0.001 m ÷ 0.000001 m per µm = 1000 µm
Both units are defined exactly, so the factor is exact. Millimeter definition: millimeter; Micrometer definition: micrometer.
Worked examples
- A 0.1 mm sheet of paper is about 100 µm thick.
0.1 mm × 1000 = 100 µm - A tolerance of ±0.02 mm is ±20 µm.
0.02 mm × 1000 = 20 µm
Millimeter to Micrometer conversion table
| Millimeters (mm) | Micrometers (µm) |
|---|---|
| 0.1 mm | 100 µm |
| 0.5 mm | 500 µm |
| 1 mm | 1000 µm |
| 2 mm | 2000 µm |
| 3 mm | 3000 µm |
| 5 mm | 5000 µm |
| 6 mm | 6000 µm |
| 8 mm | 8000 µm |
| 10 mm | 10000 µm |
| 12 mm | 12000 µm |
| 15 mm | 15000 µm |
| 16 mm | 16000 µm |
| 20 mm | 20000 µm |
| 25 mm | 25000 µm |
| 25.4 mm | 25400 µm |
| 30 mm | 30000 µm |
| 50 mm | 50000 µm |
| 75 mm | 75000 µm |
| 100 mm | 100000 µm |
| 150 mm | 150000 µm |
| 300 mm | 300000 µm |
| 500 mm | 500000 µm |
| 1000 mm | 1000000 µm |
Where it's used
Small millimetre values are converted to micrometres for surface finish, coating and filter specifications. Multiply by 1000.
Millimeter to other length units
| Conversion | 1 mm equals |
|---|---|
| millimeter to meter | 0.001 m |
| millimeter to kilometer | 0.000001 km |
| millimeter to centimeter | 0.1 cm |
| millimeter to micrometer | 1000 µm |
| millimeter to nanometer | 1000000 nm |
| millimeter to angstrom | 10000000 Å |
| millimeter to mile | 6.213711922 × 10⁻⁷ mi |
| millimeter to yard | 0.001093613298 yd |
| millimeter to foot | 0.003280839895 ft |
| millimeter to inch | 0.03937007874 in |
| millimeter to mil | 39.37007874 mil |
| millimeter to nautical mile | 5.399568035 × 10⁻⁷ nmi |
Frequently asked questions
How many microns is 1 mm?
Exactly 1000 µm.
How many micrometers are in 1 millimeter?
1 mm = 1000 µm.
How do I convert millimeters to micrometers?
Multiply the value in mm by 1000. For example, 15 mm × 1000 = 15000 µm.
Is the mm to µm conversion exact?
Yes. Both units are defined exactly, and 1 mm is exactly 1000 µm.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Millimeters to Micrometers. Retrieved October 17, 2026, from https://scientificconverters.com/length/millimeters-to-micrometers/
IEEE
Scientific Converters, "Convert Millimeters to Micrometers," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/length/millimeters-to-micrometers/