Fourth root (∜) is the Unicode character at U+221C in Mathematical Operators. Official name: FOURTH ROOT. It is the radical symbol for the fourth root — not square root or cube root.
Remember
Character ∜
Unicode U+221C
Hex entity ∜
Decimal ∜
CSS escape \221C
Named entity (none)
Meaning fourth root (x^(1/4))
Not the same √ (square root) · ∛ (cube root)
Prefer ∜ or ∜ in HTML (no named form). You can also type ∜ in a UTF-8 document.
Built with Hex: ∜
Built with Decimal: ∜
Built with CSS: ∜
Typed: ∜
Equation: ∜16 = 2
Compare: ∜ vs √ vs ∛
How It Works
1. Hex:∜ inserts code point U+221C → ∜.
2. Decimal: same code point as 8732 → ∜. Same visual as hex.
3. CSS: use \221C in content (not an HTML entity). #point::after appends ∜.
4. Typed: paste ∜ in a UTF-8 document when you need the fourth-root radical as one character.
Pitfalls & Tips
Common mistakes when working with fourth root.
Name
No named entity
There is no HTML5 named entity for U+221C. Use ∜ or ∜. Do not invent &fourthroot;. Square root uses √.
√
Not square root
Square root is √ (√, U+221A). Use it only for √x, not for fourth roots.
∛
Not cube root
Cube root is ∛ (U+221B). Pick the radical that matches the root degree.
Layout
Plain text vs MathML
U+221C is a single character. For complex nested expressions, prefer MathML or a math renderer.
CSS vs HTML
Do not mix escapes
\221C belongs in CSS strings. ∜ / ∜ belong in HTML.
a11y
Add accessible text
Screen readers may not announce ∜ clearly. Prefer nearby prose (for example “fourth root of 16”) when the symbol carries meaning.
Semicolon
End references
Always finish entities with ; — write ∜, not ∜.
Compatibility
Browser Support
Fourth root (U+221C) and its entity forms (∜, ∜, CSS \\221C) are supported in all mainstream browsers. Visible glyphs depend on Mathematical Operators font coverage.
✓ Universal support
Fourth Root (∜)
Encode with hex, decimal, CSS escape, or type the character — same code point everywhere encoding is supported.
100%Browser coverage
Google ChromeSupported
Yes
Microsoft EdgeSupported
Yes
Mozilla FirefoxSupported
Yes
Apple SafariSupported
Yes
OperaSupported
Yes
Internet ExplorerAll versions
Yes
U+221CFull support
Bottom line: Prefer ∜ in HTML (no named form). Use ∜ when decimal form is required, and \\221C only inside CSS content.
Remember
Key Takeaways
Unicode: fourth root is U+221C (decimal 8732) — glyph ∜.
HTML: no named entity — use ∜ / ∜ / type ∜.
CSS: use \221C inside content for generated text.
Meaning: ∜ = fourth root · √ = square · ∛ = cube.
One line:U+221C → ∜ / ∜ / CSS \221C (no named form).
Frequently Asked Questions
Use ∜ (hex), ∜ (decimal), type ∜ directly in UTF-8, or the CSS escape \221C in content. There is no named HTML entity for U+221C.
U+221C (FOURTH ROOT). Hex 221C, decimal 8732. It belongs to the Mathematical Operators block (U+2200–U+22FF).
No. HTML5 does not define a named entity for U+221C. Prefer ∜ or ∜. Square root does have √.
Use it in math and education when you need the fourth-root radical. Use square root (U+221A) or cube root (U+221B) for those degrees instead.
HTML numeric entities (∜ or ∜) go in markup. The CSS escape \221C goes in stylesheet strings (usually content on ::before/::after).
No. Fourth root is U+221C (∜). Square root is U+221A (√, √). Cube root is U+221B (∛).
🤔
Did you know?
Fourth root is Unicode U+221C (decimal 8732) — glyph ∜ (FOURTH ROOT) in Mathematical Operators. There is no HTML5 named entity; use ∜ or ∜. It is the radical for the fourth root (x1/4). Do not confuse it with square root (√, √) or cube root (∛).
