What is micrometre?
A micrometre, also called a micron, is a unit of length equal to one millionth of a metre. It is used in microscopy, semiconductor fabrication, and the measurement of fine particles and biological cells.
Real-world uses
Micrometres (microns) are used to measure biological cells, bacteria, semiconductor chip features, and fine particle sizes in air quality monitoring. Paint film thickness, fibre diameters, and precision machining tolerances are also specified in µm.
History
The micrometre was formalized with SI prefix standardization in the 20th century. The term "micron" was officially revoked by the SI in 1967 in favour of "micrometre," though "micron" persists informally in many industries.
Common mistakes
Using the symbol "u" instead of the correct "µ" (Greek mu). Also, confusing micrometres with nanometres—a human hair is about 70 µm wide, not 70 nm.
What is metre?
The metre is the SI base unit of length. It is used globally in science, engineering, geography, and everyday measurement as the standard reference for distance.
Real-world uses
The metre is the standard unit for everyday measurements worldwide, from room dimensions and furniture sizes to athletic track events like the 100 m sprint. Engineers, architects, and scientists use it as the fundamental length reference in the SI system.
History
Originally defined in 1793 during the French Revolution as one ten-millionth of the distance from the North Pole to the equator along a meridian through Paris. Since 1983, it is defined by the speed of light in vacuum.
Common mistakes
Confusing "meter" (the measuring device) with "metre" (the unit of length) in British English. Also, people sometimes incorrectly assume 1 metre equals exactly 3 feet; it is actually about 3.281 feet.
When is this conversion used?
This conversion is frequently needed in construction, architecture, and real estate where building codes may specify dimensions in one system while materials are sold in another.
Worked examples
1 micrometre = 0.000001 metre
1 metre = 1 metre
How to convert micrometre to metre
To convert micrometre to metre, multiply the value by 0.000001.
To convert metre back to micrometre, multiply by 1,000,000.
Measurement standards
The metre is one of seven SI base units, maintained by the International Bureau of Weights and Measures (BIPM). Since 2019, it is defined by fixing the numerical value of the speed of light in vacuum to exactly 299,792,458 metres per second.
Did you know?
A human hair is roughly 70 micrometres wide, while a single gold atom measures about 0.144 nanometres in diameter — meaning you could line up nearly half a million atoms across the width of one hair.
Quick reference: micrometre to metre
| micrometre | metre |
|---|---|
| 0.1 | 1.000000e-07 |
| 0.5 | 5.000000e-07 |
| 1 | 0.000001 |
| 2 | 0.000002 |
| 5 | 0.000005 |
| 10 | 0.00001 |
| 25 | 0.000025 |
| 50 | 0.00005 |
| 100 | 0.0001 |
| 250 | 0.00025 |
| 500 | 0.0005 |
| 1,000 | 0.001 |
Common values
| micrometre | metre | |
|---|---|---|
| Height of a door | 2,100,000 micrometre | 2.1 metre |
| Basketball court length | 28,000,000 micrometre | 28 metre |
| Football field (soccer) | 105,000,000 micrometre | 105 metre |
| Marathon distance | 4.219500e+10 micrometre | 42,195 metre |
| Altitude of a cruising airplane | 1.066800e+10 micrometre | 10,668 metre |