HTML Entity for Not Element Of (∉)

Beginner

5 min read

Updated: Sep 2026

1 example

Unicode U+2209

HTML Entity for not element of (U+2209) tutorial illustration

Definition

What Is the Not Element Of Entity?

Not element of (∉) is the Mathematical Operators character at Unicode U+2209 (NOT AN ELEMENT OF). It states that an object is not a member of a set — for example x ∉ A.

Remember

Character     ∉
Unicode       U+2209
Named entity  &notin;  (also &notinva;, &NotElement;)
Hex entity    &#x2209;
Decimal       &#8713;
CSS escape    \2209
Affirmative   &isin; (∈, U+2208)

Named, hex, decimal, CSS, and a typed character all produce the same glyph: ∉. Prefer ∉ in HTML source for clarity.

Reference

Quick Reference

One table for every form you will actually use.

Form	Code	Where it goes
Named entity	`∉`	HTML markup (also `&notinva;`)
Hex entity	`∉`	HTML markup
Decimal entity	`∉`	HTML markup
CSS escape	`\2209`	Stylesheet `content`
Direct character	`∉`	UTF-8 HTML text

When to Use Which

Situation	Use
Readable HTML source	`∉` or `&notinva;`
Numeric entity required	`∉` or `∉`
Generated text via `::before` / `::after`	`content: "\2209"`
Element of ∈	`∈` — see Element Of
Strict not equal ≠	`≠`

See it

Live Preview

Not element of in set-membership contexts.

Relation x ∉ A

Large glyph ∉

Named entity ∉ → ∉

vs ∈ / ≠ ∉ | ∈ | ≠

With entities Named: ∉ | Hex: ∉ | Decimal: ∉

Code

Complete HTML Example

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

Named + Hex + Decimal + CSS

Four ways to produce ∉ in a single document.

html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Not Element Of (&notin;)</title>
  <style>
    #point::after {
      content: "\2209";
    }
  </style>
</head>
<body>
  <p>Using Named Entity: &notin;</p>
  <p>Using Hex Code: &#x2209;</p>
  <p>Using HTML Code: &#8713;</p>
  <p id="point">Using CSS Entity: </p>
  <p>Example: 5 &notin; {1, 2, 3, 4}</p>
</body>
</html>

Try It Yourself

How It Works

1. Named: ∉ (or &notinva;) is the clearest HTML form and renders ∉.

2. Hex: U+2209 → ∉ in HTML. Same result as the named entity.

3. Decimal: same code point as 8713 → ∉. Same result as hex.

4. CSS: use \2209 in content (not an HTML entity). #point::after appends that ∉ after the paragraph text.

Pitfalls & Tips

Common mistakes when working with the not-element-of entity.

Pair

`∉` ≠ `∈`

∉ is the negation. ∈ is the affirmative element of (∈).

Look-alikes

Not `≠` or `&nsub;`

≠ is ≠ (not equal). &nsub; is ⊄ (not a subset). Membership and equality/subset are different relations.

Aliases

`∉` = `&notinva;`

Both (and &NotElement;) map to U+2209. Pick one and stay consistent.

CSS vs HTML

Do not mix escapes

\2209 belongs in CSS. ∉ / ∉ / ∉ belong in HTML.

Encoding

Declare UTF-8

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

Semicolon

End references

Always finish with ; — write ∉, not &notin.

Compatibility

Browser Support

Not element of (U+2209) and its entity forms (∉, ∉, ∉, CSS \\2209) are supported in all modern browsers. Glyph availability depends on the font.

✓ Universal encoding

Not Element Of (∉)

Encode with named, hex, decimal, or CSS escape — or paste ∉ 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 All versions

Yes

U+2209 Full support

Bottom line: Prefer ∉ (or &notinva;) for readable HTML. Use \\2209 only inside CSS content.

Remember

Key Takeaways

Unicode: this character is U+2209 (decimal 8713).
HTML: prefer ∉ (alias &notinva;) — or use ∉ / ∉.
CSS: use \2209 inside content for generated text.
Watch out: ∉ ≠ ∈ ≠ ≠.

One line: U+2209 → ∉ / ∉ / ∉ / CSS \2209.

Frequently Asked Questions

How do I display not element of (∉) in HTML using entities?

Use ∉ or &notinva; (named), ∉ (hex), ∉ (decimal), type ∉ in UTF-8, or the CSS escape \2209 in content. All render ∉. Prefer ∉ in HTML source.

What is the Unicode value for notin?

U+2209 (NOT AN ELEMENT OF). Hex 2209, decimal 8713. It belongs to the Mathematical Operators block (U+2200–U+22FF).

Is there a named HTML entity for U+2209?

Yes. HTML5 defines ∉, &notinva;, and &NotElement; (aliases for the same character). Related: ∈ for ∈ (U+2208).

When should I use this HTML entity?

Use it when an object is not a member of a set (e.g. 5 ∉ {1, 2, 3}). Prefer ∉ for readable source. For membership use ∈ (∈).

What is the difference between HTML code and CSS entity for U+2209?

HTML entities (∉, ∉, or ∉) go in markup. The CSS escape \2209 is used in stylesheets (usually in the content property of ::before/::after). Both render ∉.

How is ∉ different from ∈ or ≠?

∈ (U+2208, ∈) means element of. ≠ (U+2260, ≠) means not equal. ∉ (∉) specifically means not an element of a set — do not substitute one for another.

Did you know?

Not element of (∉) is Unicode U+2209 (decimal 8713) — NOT AN ELEMENT OF in Mathematical Operators. HTML5 provides ∉, &notinva;, and &NotElement; (same glyph). It negates element of (∈, ∈, U+2208).

Next: Not Equal To

Learn the HTML entity for ≠ / U+2260 — next in this sequence.

Continue tutorial →

About the author

Mari Selvan M P 🔗

Developer, cloud engineer, and technical writer

Experience 12 years building web and cloud systems
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I write practical tutorials so students and working developers can learn by doing—from databases and APIs to deployment on AWS.

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