Hook Above is the Unicode character at U+0309 in Combining Diacritical Marks. Official name: COMBINING HOOK ABOVE. It is a combining mark that attaches to the previous base letter — for example ả → ả. In Vietnamese it marks the hỏi tone (dấu hỏi).
Remember
Mark (combining U+0309)
Example ả
Unicode U+0309
Hex entity ̉
Decimal ̉
CSS escape \0309
Named entity (none)
Needs a base letter before the mark
Prefer when precomposed ả (U+1EA3) exists
Prefer ̉ or ̉after a base letter (no named form). For everyday Vietnamese, prefer precomposed letters such as ả (ả) when available.
Reference
Quick Reference
One table for every form you will actually use.
Form
Code
Where it goes
Named entity
None
—
Hex entity
̉
After a base letter in HTML
Decimal entity
̉
After a base letter in HTML
Precomposed (preferred)
ả (ả) and related letters
Everyday Vietnamese text
CSS escape
\0309
Stylesheet content with a base letter
When to Use Which
Situation
Use
Vietnamese hỏi tone with a precomposed letter
Precomposed form (e.g. ả → ả) plus visible text or lang="vi"
Hook Above rendered with base letters, next to a precomposed Vietnamese form.
Built with U+0309ả ẻ ỏ ủ
Precomposedả ẻ ỏ ủ
Large sampleả
Comparedả ả ä å
With entitiesHex: ả | Decimal: ả | Precomposed: ả
Code
Complete HTML Example
One page that shows Hook Above with hex, decimal, CSS escape, a typed combining sequence, and a precomposed alternative. Use View Output or open the live editor.
Hex + Decimal + CSS + Typed + Precomposed
Ways to work with U+0309 and the preferred precomposed ả.
html
<!DOCTYPE html>
<html lang="vi">
<head>
<meta charset="UTF-8">
<title>Hook Above (U+0309) in HTML</title>
<style>
#point::after {
content: "a\0309";
}
</style>
</head>
<body>
<p>Built with Hex: ả</p>
<p>Built with Decimal: ả</p>
<p id="point">Built with CSS: </p>
<p>Typed: ả</p>
<p>Precomposed (preferred): ả</p>
<p><span aria-label="a with Hook Above">ả</span></p>
</body>
</html>
Built with Hex: ả
Built with Decimal: ả
Built with CSS: ả
Typed: ả
Precomposed (preferred): ả
ả
How It Works
1. Hex: write a base letter, then ̉. The mark combines → ả.
2. Decimal: same mark as 777 → ả. Same visual as hex.
3. CSS: put the base letter and \0309 together in content (e.g. "a\0309"). Combining alone in content has nothing to attach to.
4. Precomposed:ả is one character (U+1EA3 → ả). Prefer this for everyday Vietnamese ả.
Pitfalls & Tips
Common mistakes when working with Hook Above.
Order
Base letter first
Always write the base character before ̉. Alone, U+0309 may not display usefully.
Name
No named entity
There is no HTML5 named entity for U+0309. Use ̉ or ̉, or a precomposed letter such as ả.
ả
Prefer precomposed Vietnamese
For common hỏi-tone letters (ả ẻ ỉ ỏ ủ ỷ …), prefer the single precomposed code point over building with U+0309.
Font
Font coverage
Some fonts stack combining marks poorly. If ả looks wrong, try a font with good Vietnamese / Combining Diacritical Marks support.
CSS vs HTML
Do not mix escapes
\0309 belongs in CSS strings (with a base letter). ̉ / ̉ belong in HTML after a base letter.
a11y
Add accessible text
Prefer lang="vi" on Vietnamese content and clear prose. Use aria-label when a rare combining sequence could be unclear.
Semicolon
End references
Always finish entities with ; — write ̉, not ̉.
Compatibility
Browser Support
Hook Above (U+0309) and its entity forms (̉, ̉, CSS \\0309) are supported in all mainstream browsers. Visible combining depends on font coverage for Combining Diacritical Marks and Vietnamese letters.
✓ Universal support
Hook Above (U+0309)
Encode with hex, decimal, CSS escape, type the mark after a base letter, or use a precomposed Vietnamese letter — encoding is supported everywhere.
100%Browser coverage
Google ChromeSupported
Yes
Microsoft EdgeSupported
Yes
Mozilla FirefoxSupported
Yes
Apple SafariSupported
Yes
OperaSupported
Yes
Internet ExplorerAll versions
Yes
U+0309Full support
Bottom line: Prefer precomposed Vietnamese letters when available. Otherwise use ̉ after a base letter (no named form), and \\0309 only inside CSS content with a base letter.
Remember
Key Takeaways
Unicode: Hook Above is combining U+0309 (decimal 777) — needs a base letter.
HTML: no named entity — use ả / ả, or prefer ả (ả).
CSS: use "a\0309" inside content (base letter + escape).
Meaning: Vietnamese hỏi tone mark — prefer precomposed letters when they exist.
One line: base + U+0309 → ả / CSS "a\0309", or prefer ả (ả).
Frequently Asked Questions
Write a base letter, then ̉ (hex), ̉ (decimal), or use CSS content with a base letter plus \0309 (for example "a\0309"). There is no named HTML entity for U+0309. For Vietnamese ả, prefer the precomposed character ả when possible.
U+0309 (COMBINING HOOK ABOVE). Hex 0309, decimal 777. It belongs to the Combining Diacritical Marks block (U+0300–U+036F).
No. HTML5 does not define a named entity for this combining mark. Prefer ̉ or ̉ after a base letter, or a precomposed Vietnamese letter such as ả (ả).
Use it for Vietnamese tone (dấu hỏi) or linguistics when you need Hook Above on a letter that has no convenient precomposed form. Prefer NFC / precomposed Vietnamese letters (ả ẻ ỉ ỏ ủ ỷ …) for everyday text.
HTML numeric entities (̉ or ̉) go in markup after a base letter. The CSS escape \0309 goes in stylesheet strings together with a base letter (usually content on ::before/::after).
Related, but not the same encoding. a + U+0309 builds a combining sequence. ả (U+1EA3) is one precomposed character. Prefer the precomposed form for Vietnamese when available.
🤔
Did you know?
Hook Above is Unicode U+0309 (decimal 777) in Combining Diacritical Marks (official name COMBINING HOOK ABOVE). It is a combining mark that attaches to the previous character (e.g. ả → ả). There is no HTML5 named entity. For Vietnamese, prefer precomposed letters such as ả (U+1EA3 / ả) when they exist.
