---
title: "Micrometers to Millimeters — µm to mm converter"
description: "1 micrometer = 0.001 millimeters. Convert micrometers to millimeters with a full conversion table, the exact formula, and a calculator for any value."
url: https://atoneplace.net/convert/microns-to-mm/
site: "At One Place"
---

# Micrometers to millimeters

**1 micrometer in millimeters: 1 µm = 0.001 mm**

mm = µm × 0.001

To convert micrometers to millimeters, multiply by 0.001. The table below gives the values people look up most often, and the converter works for any number.

## Micrometers to millimeters table

*Common micrometer values converted to millimeters.*

| Micrometers | Millimeters |
| --- | --- |
| 1 µm | 0.001 |
| 2 µm | 0.002 |
| 3 µm | 0.003 |
| 4 µm | 0.004 |
| 5 µm | 0.005 |
| 10 µm | 0.01 |
| 15 µm | 0.015 |
| 20 µm | 0.02 |
| 25 µm | 0.025 |
| 30 µm | 0.03 |
| 40 µm | 0.04 |
| 50 µm | 0.05 |
| 75 µm | 0.075 |
| 100 µm | 0.1 |
| 250 µm | 0.25 |
| 500 µm | 0.5 |
| 1,000 µm | 1 |

## How the conversion works

The relationship is mm = µm × 0.001. Both units measure length, so the conversion is a fixed factor that never changes.

## Common questions

### How many millimeters are in one micrometer?

One micrometer equals 0.001 millimeters. mm = µm × 0.001.

### How do you convert micrometers to millimeters?

Use mm = µm × 0.001. So 10 µm is 0.01 mm.

### How many micrometers are in one millimeter?

One millimeter equals 1,000 micrometers, which is the reverse of the conversion above.

## Related pages

- [Millimeters to Micrometers](https://atoneplace.net/convert/mm-to-microns/)
- [Micrometers to Meters](https://atoneplace.net/convert/microns-to-meters/)
- [Micrometers to Kilometers](https://atoneplace.net/convert/microns-to-km/)
- [Micrometers to Centimeters](https://atoneplace.net/convert/microns-to-cm/)
- [Micrometers to Miles](https://atoneplace.net/convert/microns-to-miles/)
- [Micrometers to Yards](https://atoneplace.net/convert/microns-to-yards/)
- [Micrometers to Feet](https://atoneplace.net/convert/microns-to-feet/)
- [Micrometers to Inches](https://atoneplace.net/convert/microns-to-inches/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)