Micrometre facts for kids

A carbon filament, which is 6 micrometres wide, next to a human hair, which is 50 micrometres wide.

A micrometre is a very, very small unit of length. It's part of the SI measurement system, which is used all over the world. You might also hear it called a micron. The symbol for a micrometre is µm.

Imagine taking one metre and dividing it into a million equal pieces. One of those tiny pieces is a micrometre! It's so small that you can't see it with just your eyes.

What is a Micrometre?

A micrometre is a unit of measurement that helps us talk about things that are incredibly small. It's used when we need to measure the size of tiny objects, much smaller than what you can see.

How Small is a Micrometre?

To give you an idea of how small a micrometre is:

• A single human hair is about 50 to 100 micrometres thick.
• A red blood cell, which carries oxygen in your body, is about 6 to 8 micrometres wide.
• Many types of bacteria are only a few micrometres long.
• Dust particles can be around 10 to 50 micrometres in size.

Because it's so tiny, micrometres are often used in science. Scientists use them to measure cells, viruses, and other microscopic things.

Images for kids

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  This picture helps you see how small 1 micrometre is compared to other things.

See also

In Spanish: Micrómetro (unidad de longitud) para niños