HTML Entity for Lowercase O Horn (ơ)

Beginner
⏱️ 5 min read
📚 Updated: Jun 2026
🎯 1 Code Example
Unicode U+01A1
HTML Entity for Lowercase O Horn tutorial illustration

What You'll Learn

How to display the lowercase o with horn (ơ) in HTML using hexadecimal, decimal, and CSS escape methods. This character is U+01A1 in the Latin Extended-B block. The horn diacritic is essential in Vietnamese, where ơ is one of the twelve vowel letters and represents a distinct mid-central vowel sound.

Render it with ơ, ơ, or CSS escape \01A1. There is no named HTML entity for this character. In UTF-8 documents you can also type ơ directly.

⚡ Quick Reference — Lowercase O Horn Entity

Unicode U+01A1

Latin Extended-B

Hex Code ơ

Hexadecimal reference

HTML Code ơ

Decimal reference

Named Entity —

No named entity

Reference Table
Name           Value
────────────   ──────────
Unicode        U+01A1
Hex code       ơ
HTML code      ơ
Named entity   (none)
CSS code       \01A1
Meaning        Latin small letter o with horn
Related        U+01A0 = Ơ (uppercase)
Block          Latin Extended-B (U+0180–U+024F)
1

Complete HTML Example

A simple example showing the lowercase o horn (ơ) using hexadecimal code, decimal HTML code, the character directly, and a CSS content escape:

html
<!DOCTYPE html>
<html>
<head>
 <style>
  #point:after{
   content: "\01A1";
  }
 </style>
</head>
<body>
<p>Symbol (hex): &#x01A1;</p>
<p>Symbol (decimal): &#417;</p>
<p>Symbol (direct): ơ</p>
<p id="point">Symbol (CSS): </p>
</body>
</html>
Try It Yourself

🌐 Browser Support

The lowercase o horn (ơ) is supported in all modern browsers as part of Latin Extended-B:

Chrome1+
Firefox1+
Safari1+
Edge12+
Opera4+
Android4.4+
iOS Safari1+

👀 Live Preview

See the lowercase o horn (ơ) in Vietnamese contexts:

Large glyphơ
Vietnamesebơ  |  cơm  |  mơ
With tone marksờ  |  Ớ  |  ớ  |  Ờ  |  ợ
UppercaseƠ (U+01A0) — LATIN CAPITAL LETTER O WITH HORN
Not the same asô (circumflex)  |  o (plain)  |  ò (grave)
Numeric refs&#x01A1; &#417; \01A1

🧠 How It Works

1

Hexadecimal Code

&#x01A1; uses the Unicode hexadecimal value 01A1 to display the character. The x prefix indicates hexadecimal format.

HTML markup
2

Decimal HTML Code

&#417; uses the decimal Unicode value 417 to display the same character. A common method when a numeric reference is needed.

HTML markup
3

Direct Character

Type ơ directly in HTML when your document uses UTF-8 encoding. There is no named entity for this Vietnamese vowel.

HTML markup
4

CSS Entity

\01A1 is used in CSS stylesheets, particularly in the content property of pseudo-elements like ::before and ::after.

CSS stylesheet
=

Same visual result

All methods produce the glyph: ơ. Unicode U+01A1 sits in Latin Extended-B. Uppercase equivalent: U+01A0 (Ơ). In Vietnamese, ơ can combine with tone marks (e.g. ờ, Ớ, ớ, Ờ, ợ). Do not confuse with ô (circumflex).

✅

Use Cases

The lowercase o horn (ơ) is commonly used in:

🇻🇳 Vietnamese Content

Essential for correct spelling in Vietnamese (bơ, cơm, mơ). ơ is a distinct vowel, not interchangeable with o or ô.

📚 Dictionaries

Headwords, definitions, and pronunciation guides for Vietnamese words containing ơ.

📝 Language Learning

Lessons, flashcards, and vocabulary content for Vietnamese learners showing the correct ơ character.

🌐 Multilingual Sites

Vietnamese versions of websites, product names, place names, and localized user content.

📰 Publishing

Articles, news, and formal documents that require correct Vietnamese typography.

♿ Accessibility

Using U+01A1 with lang="vi" ensures assistive technologies interpret Vietnamese text correctly.

⚙ Programmatic HTML

When building HTML from translation data, using &#417; or &#x01A1; guarantees correct output.

💡 Best Practices

Do

  • Serve pages as UTF-8; you can type ơ directly in UTF-8 source
  • Use numeric references (&#x01A1; or &#417;) when escaping is required
  • Set lang="vi" on Vietnamese content blocks
  • Use fonts that support Latin Extended-B (U+0180–U+024F)
  • Distinguish ơ (horn) from ô (circumflex) and plain o

Don’t

  • Substitute plain o or ô when ơ is required in Vietnamese
  • Confuse ơ (horn) with ô (circumflex)—they are different vowels
  • Expect a named HTML entity—none exists for ơ
  • Put CSS escape \01A1 in HTML text nodes
  • Double-encode numeric references in dynamically generated HTML

Key Takeaways

1

Type ơ directly, or use hex/decimal references

&#x01A1; &#417;
2

For CSS stylesheets, use the escape in the content property

\01A1
3

Unicode U+01A1 — LATIN SMALL LETTER O WITH HORN

4

Essential for Vietnamese; uppercase is Ơ (U+01A0)

5

Previous: Lowercase O Grave (ò)   Next: Lowercase O Inverted Breve

❓ Frequently Asked Questions

Use &#x01A1; (hex), &#417; (decimal), or \01A1 in CSS content. There is no named HTML entity for ơ. In UTF-8 you can also type ơ directly.
U+01A1 (LATIN SMALL LETTER O WITH HORN). Latin Extended-B block. Hex 01A1, decimal 417. Essential for Vietnamese orthography. Uppercase form is U+01A0 (Ơ).
When displaying Vietnamese text, dictionaries, language learning content, or any page that requires the distinct vowel ơ. It is not interchangeable with plain o or ô (o circumflex).
No. There is no named HTML entity for ơ. Use numeric codes &#417; or &#x01A1;, or the CSS entity \01A1. In UTF-8 pages you can type ơ directly.
ơ (U+01A1) is o with horn, a distinct mid-central vowel. ô (U+00F4) is o with circumflex, a different vowel (e.g. cô vs cơ). Using the wrong character changes meaning and pronunciation.

Explore More HTML Entities!

Discover 1500+ HTML character references — letters, symbols, and more.

All HTML Entities →

About the author

Mari Selvan M P
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

Lowercase O Grave (ò) Lowercase O Inverted Breve