Mu Symbol Copy and Paste (μ Μ)
Greek small mu
Unicode U+03BC · HTML μ
Tap any symbol to copy it. Each tap also adds it to the box above, so you can copy several together.
Codes for every symbol on this page (Unicode, HTML, Alt, Mac, Word)
| Symbol | Name | Unicode | HTML | Windows Alt code | Mac | MS Word |
|---|---|---|---|---|---|---|
| μ | Greek small mu | U+03BC | μ | - | - | 03BC then Alt+X |
| Μ | Greek capital mu | U+039C | Μ | - | - | 039C then Alt+X |
| µ | Micro sign (units) | U+00B5 | µ | Alt+230, Alt+0181 | Option+M | 00B5 then Alt+X |
The mu symbol μ is the 12th letter of the Greek alphabet. Students write it for the coefficient of friction in physics, for the population mean in statistics, and for magnetic permeability in electromagnetism.
This page is about the Greek letter itself. There is also a look-alike character called the micro sign (µ), which is meant for units such as µm and µg. If you are writing units, go to the micro symbol page. Tap any symbol in the grid to copy it.
Mu Symbol in Physics
The mu symbol in physics has several jobs. Here are the ones you will see in Class 11, Class 12 and first-year college:
| Where | Meaning of μ | Example |
|---|---|---|
| Mechanics | Coefficient of friction | f = μN |
| Magnetism | Permeability of a material | B = μH |
| Magnetism | μ₀, permeability of free space | about 4π × 10⁻⁷ H/m |
| Optics (many Indian books) | Refractive index | μ = c ÷ v |
| Atomic physics | Magnetic moment | μ of a current loop = I A |
| Mechanics | Reduced mass | μ = m₁m₂ ÷ (m₁ + m₂) |
Because one letter carries so many meanings, always read the chapter heading. In a friction problem μ has no unit; in magnetism it does.
Coefficient of Friction Symbol: μs and μk
The coefficient of friction symbol is μ. It is a pure number with no unit, found by dividing the friction force by the normal force.
- μs (static): friction just before an object starts to slide.
- μk (kinetic): friction while the object is already sliding. Usually μk is smaller than μs.
Example: a 10 kg box rests on a floor with μs = 0.4. The normal force is about 98 N, so you need roughly 0.4 × 98 ≈ 39 N to start pushing it.
Population Mean Symbol in Statistics
In statistics, μ is the population mean symbol. It is the average of every member of a whole group. The average of a smaller sample is written x̄ (x-bar).
- μ = average height of all Class 10 students in India (population).
- x̄ = average height of 50 students you actually measured (sample).
You will often see μ with σ, the population standard deviation, as in "normal distribution with mean μ and standard deviation σ". See the sigma symbol page for σ.
Mu Not Symbol (μ₀) Explained
When people search "mu not symbol", they mean mu naught, written μ₀. "Naught" means zero, so μ₀ is "mu zero". It is the magnetic permeability of empty space, a constant that appears in Biot-Savart law and Ampere's law.
To write it in Word, type μ, then 0, select the 0 and press Ctrl+= to make it subscript. In a Word equation, type \mu_0 followed by a space. Its partner constant ε₀ is covered on the epsilon symbol page.
How to Type the Mu Symbol in Keyboard Shortcuts
The Greek μ (U+03BC) has no Alt code and no Mac Option key. Use these instead:
- Word: type
03BCand press Alt+X. For capital Μ, use039C. - Google Docs: Insert > Special characters, search "mu" and pick Greek small letter mu.
- Excel: type
=UNICHAR(956)in a cell. - Mac: open Character Viewer with Control+Command+Space and search "mu".
- Phone: add a Greek keyboard, or copy from the grid above.
Many people press Alt+230 or Option+M for the mu symbol in keyboard shortcuts. These give the micro sign µ, not Greek μ. They look the same in most fonts, which is fine for a quick note, but for equations and maths software the Greek letter is the correct choice.
Mu (μ) vs Micro Sign (µ)
| Greek mu μ | Micro sign µ | |
|---|---|---|
| Code point | U+03BC | U+00B5 |
| Use | Variables: friction, mean, permeability | Unit prefix: µm, µg, µF |
| Alt code | None | Alt+0181, Alt+230 |
| Mac | Character Viewer | Option+M |
The micro sign exists mainly because older computer character sets had it before Unicode. Unicode treats the two as related, but they are still separate characters. Capital Μ, by the way, looks exactly like the English letter M, so it is rarely used in science. More Greek letters are on our Greek letters hub.
Frequently asked questions
What is the symbol of mu?
The symbol of mu is μ in small letters and Μ in capital letters. In science, the small form μ is almost always the one you need.
How is mu pronounced?
In Indian and British English it is usually said "myoo", rhyming with "new". In modern Greek it sounds like "mee".
Is the mu meter symbol written with μ?
When people say "mu meter" they mean the micrometre, written µm. That is a unit prefix, and this site uses the micro sign µ for it, but you will also see μm with Greek mu in books and papers. Both are read the same way.
Does μ for friction have a unit?
No. The coefficient of friction is a ratio of two forces, so the units cancel. Write μ = 0.3, not 0.3 N.
What number did mu represent in Greek numerals?
In the ancient Greek number system, μ stood for 40. Today it is used only as a letter and a scientific symbol.