Alt Codes & Keyboard Shortcuts
Micro Sign
The SI prefix for one millionth, as in µm and µs.
µ
- Windows
- Alt + 0181
- Mac
- Option + M
- Unicode
- U+00B5
Try Micro Sign
Edit the text, then change the font and size.
About this entry
What it is
The SI prefix for one millionth, as in µm and µs.
Scientific and engineering units where writing “micro” would be clumsy.
Copy & use
How to copy and use micro sign
- 01
Copy the complete value
Use the copy button above so the value is captured without its label, description or surrounding page text.
- 02
Paste it where you need it
Scientific and engineering units where writing “micro” would be clumsy.
- 03
Check the final result
Windows Alt codes may require a numeric keypad and Num Lock. Laptop keyboards, browser fields and regional layouts can behave differently, so copying is the dependable fallback.
What it is for
When to reach for µ
The micro sign is the SI prefix for one millionth: µm, µs, µg. There are two nearly identical characters for it and the distinction matters in data.
Getting the shortcut to work
Because two characters exist, a search for one will miss text containing the other — worth normalising before comparing data. The Windows code needs the numeric keypad with Num Lock on — the number row above the letters will not work. On a laptop without a keypad, use the copy button above or Windows Character Map.
Easily confused
Characters that look like µ
These are separate characters. They may look almost identical on screen, but they sort, search and compare differently.
Greek small letter mu
A different code point, U+03BC. Unicode prefers it for the SI prefix, but the legacy micro sign is what most keyboards produce. They do not compare as equal.
Common questions
Using micro sign
What is micro sign?
The SI prefix for one millionth, as in µm and µs. Scientific and engineering units where writing “micro” would be clumsy.
How do I type Micro Sign without copying it?
On Windows: Alt + 0181. On macOS: Option + M. Windows Alt codes need the numeric keypad with Num Lock on, so laptops without one are usually quicker to serve by the copy button above.
Will micro sign work everywhere?
Windows Alt codes may require a numeric keypad and Num Lock. Laptop keyboards, browser fields and regional layouts can behave differently, so copying is the dependable fallback.
Can I customise micro sign after copying?
You can add a short label, repeat compatible symbols or trim the design to fit. Keep important spaces, line breaks and uncommon Unicode characters intact while editing.
Also known as
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