HTML Entity for Micro Sign (µ)

Beginner

5 min read

Updated: Sep 2026

1 example

Unicode U+00B5

HTML Entity for micro sign (U+00B5) tutorial illustration

Definition

What Is the Micro Sign Entity?

Micro sign (µ) is Unicode U+00B5 — the SI micro prefix used in units like µm and µs. HTML5 provides the named entity µ. It is not the same code point as Greek letter mu (μ).

Remember

Character     µ
Unicode       U+00B5
Named entity  &micro;
Hex entity    &#xB5;
Decimal       &#181;
CSS escape    \00B5

Named, hex, decimal, CSS, and a typed character all produce the same glyph: µ.

Reference

Quick Reference

One table for every form you will actually use.

Form	Code	Where it goes
Named entity	`µ`	HTML markup (preferred)
Direct character	`µ`	UTF-8 HTML text
Hex entity	`µ`	HTML markup
Decimal entity	`µ`	HTML markup
CSS escape	`\00B5`	Stylesheet `content`

When to Use Which

Situation	Use
SI units (µm, µs, µg)	`µ` (clearest HTML form)
Need an entity in HTML source	`µ`, `µ`, or `µ`
Generated text via `::before` / `::after`	`content: "\00B5"`
Greek letter mu in math / Greek text	Use `μ` (μ, U+03BC) — not `µ`
ASCII fallback	Write `u` only if the micro glyph is unavailable

See it

Live Preview

Micro sign in scientific unit contexts.

Unit example 5 µm (micrometers)

Large glyph µ

Named entity µ → µ

vs Greek μ µ | μ

With entities Named: µ | Hex: µ | Decimal: µ

Code

Complete HTML Example

One page that shows the micro sign with named, hex, decimal, and CSS forms. Use View Output or open the live editor.

Named + Hex + Decimal + CSS

Four ways to produce µ in a single document.

html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Micro Sign (µ)</title>
  <style>
    #point::after {
      content: "\00B5";
    }
  </style>
</head>
<body>
  <p>Using Named Entity: &micro;</p>
  <p>Using Hex Code: &#xB5;</p>
  <p>Using HTML Code: &#181;</p>
  <p id="point">Using CSS Entity: </p>
  <p>Unit: 5 &micro;m (micrometers)</p>
</body>
</html>

Try It Yourself

How It Works

1. Named: µ is the clearest HTML form and renders µ.

2. Hex: U+00B5 → µ in HTML. Same result as the named entity.

3. Decimal: same code point as 181 → µ. Same result as hex and named.

4. CSS: use \00B5 in content (not an HTML entity). #point::after appends that µ after the paragraph text.

Pitfalls & Tips

Common mistakes when working with the micro sign.

Prefer

Use `µ`

The named entity is clearer than numeric forms and is defined in HTML5.

vs μ

Not Greek mu

µ is U+00B5 (µ). μ is U+03BC (μ). For SI units, prefer the micro sign.

Units

Keep the letter after µ

Write µm for micrometers — the m is a separate Latin letter, not part of the entity.

CSS vs HTML

Do not mix escapes

\00B5 belongs in CSS. µ / µ / µ belong in HTML.

Encoding

Declare UTF-8

If you type µ directly, keep <meta charset="UTF-8"> so the file is not misread.

Semicolon

End references

Always finish with ; — write µ, not &micro.

Compatibility

Browser Support

Micro sign (U+00B5) and its entity forms (µ, µ, µ, CSS \\00B5) are supported in all mainstream browsers.

✓ Universal support

Micro Sign (µ)

Encode with named, hex, decimal, or CSS escape — or type µ directly in UTF-8 HTML.

100% Browser coverage

Google Chrome Supported

Yes

Microsoft Edge Supported

Yes

Mozilla Firefox Supported

Yes

Apple Safari Supported

Yes

Opera Supported

Yes

Internet Explorer IE 9+

Yes*

U+00B5 / µ Full support

Bottom line: Prefer µ in HTML. Use \\00B5 only inside CSS content.

Remember

Key Takeaways

Unicode: micro sign is U+00B5 (decimal 181).
HTML: prefer µ (also µ / µ).
CSS: use \00B5 inside content for generated text.
Do not confuse: Greek mu is μ (μ, U+03BC).

One line: U+00B5 → prefer µ (also µ / µ / CSS \00B5).

Frequently Asked Questions

How do I display the micro sign in HTML using entities?

Use µ (named), µ (hex), µ (decimal), or the CSS escape \00B5 in the content property. All render µ. Prefer µ in HTML source.

What is the Unicode value for the micro sign?

U+00B5 (MICRO SIGN). Hex 00B5, decimal 181. It belongs to the Latin-1 Supplement block.

Is there a named HTML entity for U+00B5?

Yes. µ is the HTML5 named entity for µ.

When should I use this HTML entity?

Use it for SI micro prefixes such as micrometers (µm), microseconds (µs), and micrograms (µg) in scientific and technical content.

What is the difference between HTML code and CSS entity for U+00B5?

HTML entities (µ, µ, or µ) go in markup. The CSS escape \00B5 is used in stylesheets (usually in the content property of ::before/::after). Both render µ.

Is µ the same as Greek mu μ?

No. Micro sign is µ (µ, U+00B5). Greek small letter mu is μ (μ, U+03BC). They look similar; for SI units, prefer µ.

Did you know?

Micro sign is Unicode U+00B5 (decimal 181) — MICRO SIGN in Latin-1 Supplement. HTML5 provides µ. Prefer it for SI micro prefixes (µm, µs). Greek letter mu is a different character: μ (μ, U+03BC).

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About the author

Mari Selvan M P 🔗

Developer, cloud engineer, and technical writer

Experience 12 years building web and cloud systems
Focus Full Stack Development, AWS, and Developer Education

I write practical tutorials so students and working developers can learn by doing—from databases and APIs to deployment on AWS.

AWS Certified Developer – Associate (Credly)

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