Convert Micrometre to Millimetre
1 micrometre = 0.001 millimetre (mm). For example, 10 micrometre = 0.01 millimetre and 100 micrometre = 0.1 millimetre. Type any value below to convert micrometre to millimetre both ways — it runs entirely in your browser.
Micrometre to Millimetre conversion formula
To convert micrometre to millimetre, multiply by 0.001:
millimetre = micrometre × 0.001
Going the other way, 1 millimetre = 1,000 micrometre, so
micrometre = millimetre × 1,000.
Micrometre to Millimetre — worked examples
| Micrometre | Millimetre |
|---|---|
| 1 µm | 0.001 mm |
| 2 µm | 0.002 mm |
| 3 µm | 0.003 mm |
| 5 µm | 0.005 mm |
| 10 µm | 0.01 mm |
| 25 µm | 0.025 mm |
| 50 µm | 0.05 mm |
| 100 µm | 0.1 mm |
Micrometre ↔ Millimetre reference table
| Micrometre → Millimetre | Millimetre → Micrometre |
|---|---|
| 1 µm = 0.001 mm | 1 mm = 1,000 µm |
| 2 µm = 0.002 mm | 2 mm = 2,000 µm |
| 5 µm = 0.005 mm | 5 mm = 5,000 µm |
| 10 µm = 0.01 mm | 10 mm = 10,000 µm |
| 20 µm = 0.02 mm | 20 mm = 20,000 µm |
| 50 µm = 0.05 mm | 50 mm = 50,000 µm |
| 100 µm = 0.1 mm | 100 mm = 100,000 µm |
| 250 µm = 0.25 mm | 250 mm = 250,000 µm |
| 500 µm = 0.5 mm | 500 mm = 500,000 µm |
| 1000 µm = 1 mm | 1000 mm = 1,000,000 µm |
About micrometre and millimetre
Micrometre: A micrometre (micron) is one-millionth of a metre — used for cells, wavelengths and machining tolerances.
Millimetre: A millimetre is one-thousandth of a metre.
The metric units (km, m, cm, mm, µm) are exact by definition, and the imperial units (mile, yard, foot, inch, nautical mile) use their exact international values. Traditional units (hand, span, finger, cubit, rod/pole, link, rope, ken, league) are given at their commonly accepted standard sizes — historical local values sometimes differed, so confirm against a primary source before relying on them for legal or historical work.
Frequently asked questions
- How many millimetre are in 1 micrometre?
- 1 micrometre = 0.001 millimetre (mm).
- How do I convert micrometre to millimetre?
- Multiply the number of micrometre by 0.001. For example, 10 micrometre = 10 × 0.001 = 0.01 millimetre.
- How many micrometre are in 1 millimetre?
- 1 millimetre = 1,000 micrometre.
- Which is bigger, micrometre or millimetre?
- 1 millimetre equals 1,000 micrometre, so a millimetre is the larger unit.