HTML Entity for Squared Minus (⊟)

Beginner

5 min read

Updated: Sep 2026

1 example

Unicode U+229F

HTML Entity for squared minus (U+229F) tutorial illustration

Definition

What Is Squared Minus?

Squared minus (⊟) is the Unicode character at U+229F in Mathematical Operators. Official name: SQUARED MINUS. It is a boxed (square) minus operator used in specialized math notation.

Remember

Character     ⊟
Unicode       U+229F
Named entity  &minusb;
Hex entity    &#x229F;
Decimal       &#8863;
CSS escape    \229F
Not the same  − · ⊞ · ⊠

Prefer &minusb; in HTML markup (&BoxMinus; is an alias). You can also type ⊟ in UTF-8, or use numeric forms when needed. For an ordinary minus, use − (−) instead.

Reference

Quick Reference

One table for every form you will actually use.

Form	Code	Where it goes
Named entity	`&minusb;`	HTML markup (preferred)
Alias	`&BoxMinus;`	Same glyph as `&minusb;`
Direct character	`⊟`	HTML text (UTF-8)
Hex entity	`⊟`	HTML markup
Decimal entity	`⊟`	HTML markup
CSS escape	`\229F`	Stylesheet `content`
Minus sign (related)	− (U+2212)	Named `−`

When to Use Which

Situation	Use
Squared / boxed minus	`&minusb;` or type `⊟`
Ordinary minus sign	− (`−`)
Squared plus	⊞ (`&plusb;`)
Squared times / dotted box	⊠ · ⊡
Generated text via `::before` / `::after`	`content: "\229F"`

See it

Live Preview

Squared minus rendered alone and next to related operators.

Large glyph ⊟

Notation A ⊟ B

Compared ⊟ (minusb) | − (minus) | ⊞ (plusb)

Hint Compare: Boxed ⊟ vs Minus − vs Plus ⊞

With entities Named: ⊟ | Hex: ⊟ | Decimal: ⊟

Code

Complete HTML Example

One page that shows squared minus with named, hex, decimal, CSS escape, and a typed character. Use View Output or open the live editor.

Named + Hex + Decimal + CSS + Typed

Five ways to produce ⊟, plus a short notation example.

html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Squared Minus (⊟) in HTML</title>
  <style>
    #point::after {
      content: "\229F";
    }
  </style>
</head>
<body>
  <p>Using Named Entity: &minusb;</p>
  <p>Using Hex Code: &#x229F;</p>
  <p>Using HTML Code: &#8863;</p>
  <p id="point">Using CSS Entity: </p>
  <p>Typed directly: ⊟</p>
  <p>Notation: A &minusb; B</p>
</body>
</html>

Try It Yourself

How It Works

1. Named: &minusb; is the HTML5 name for U+229F → ⊟. Best default in markup.

2. Hex: U+229F → ⊟ in HTML. Same glyph as the named form.

3. Decimal: same code point as 8863 → ⊟. Same result as hex and named.

4. CSS: use \229F in content (not an HTML entity). #point::after appends that ⊟ after the paragraph text.

5. Typed / notation: paste ⊟ in UTF-8, or write A &minusb; B for a short expression.

Pitfalls & Tips

Common mistakes when working with &minusb;.

vs −

Not an ordinary minus

U+2212 (−, −) is the common mathematical minus. U+229F is the squared (boxed) form.

vs ⊞

Not squared plus

⊞ (U+229E, &plusb;) is the plus counterpart. Do not swap them.

Name

Remember &minusb;

The named entity is &minusb; — not − (that is U+2212).

CSS vs HTML

Do not mix escapes

\229F belongs in CSS strings. &minusb; / ⊟ / ⊟ belong in HTML.

Semicolon

End named entities

Always finish with ; — write &minusb;, not &minusb.

A11y

Name the operator in context

Screen readers may announce this symbol unevenly. Prefer nearby words like “squared minus” when the glyph carries meaning alone.

Compatibility

Browser Support

Squared minus (U+229F) and its entity forms (&minusb;, ⊟, ⊟, CSS \\229F) are supported in all mainstream browsers. Visible glyphs depend on Mathematical Operators font coverage.

✓ Universal support

Squared Minus (⊟)

Encode with named, hex, decimal, CSS escape, or type the character — same code point everywhere encoding is supported.

100% Browser coverage

Google Chrome Supported

Yes

Microsoft Edge Supported

Yes

Mozilla Firefox Supported

Yes

Apple Safari Supported

Yes

Opera Supported

Yes

Internet Explorer All versions

Yes

U+229F / entities Full support

Bottom line: Prefer &minusb; in HTML. Use ⊟ / ⊟ when numeric form is required, and \\229F only inside CSS content.

Remember

Key Takeaways

Unicode: squared minus is U+229F (decimal 8863) — glyph ⊟.
HTML: prefer &minusb; — also ⊟ / ⊟ / type ⊟.
CSS: use \229F inside content for generated text.
Meaning: ⊟ is boxed minus — not − (−), not ⊞.

One line: U+229F → &minusb; / ⊟ / ⊟ / CSS \229F.

Frequently Asked Questions

How do I display ⊟ in HTML?

Use &minusb; (named), ⊟ (hex), ⊟ (decimal), type ⊟ directly in UTF-8, or the CSS escape \229F in content. Prefer &minusb; in normal HTML.

What is the Unicode value for squared minus?

U+229F (SQUARED MINUS). Hex 229F, decimal 8863. It belongs to Mathematical Operators (U+2200–U+22FF).

Is there a named HTML entity for U+229F?

Yes. Use &minusb; (or the alias &BoxMinus;). Numeric forms ⊟ and ⊟ also work.

Is ⊟ the same as − or ⊞?

No. ⊟ is U+229F (&minusb;). − is U+2212 (−). ⊞ is U+229E (&plusb;, squared plus).

When should I use &minusb;?

Use it for boxed-minus / squared-minus math notation in technical and academic pages — not as a substitute for an ordinary minus −.

What is the difference between HTML code and CSS entity for U+229F?

HTML entities (&minusb;, ⊟, or ⊟) go in markup. The CSS escape \229F goes in stylesheet strings (usually content on ::before/::after).

Did you know?

Squared minus is Unicode U+229F (decimal 8863) — glyph ⊟ in Mathematical Operators (U+2200–U+22FF). HTML5 names it &minusb; (also &BoxMinus;). Official name: SQUARED MINUS. Do not confuse with minus sign U+2212 (−, −) or squared plus U+229E (&plusb;, ⊞).

Next: Squared Plus

Learn the HTML entity for squared plus (U+229E).

Continue tutorial →

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)

8 people found this page helpful

HTML Entity | Squared Dot Operator HTML Entity | Squared Plus