U+221A · Mathematical Operators
Square Root Symbol √
The radical sign indicates the square root of a number, so √9 = 3. With a small index in front, as in ∛, it denotes other roots. It is used in math homework, engineering notes, and recipes or calculators written in plain text, where the overline bar of handwritten notation is usually replaced by parentheses.
Character codes
| Unicode code point | U+221A | |
|---|---|---|
| Decimal | 8730 | |
| HTML named entity | √ | |
| HTML (hex) | √ | |
| HTML (decimal) | √ | |
| CSS | \221A | |
| JavaScript | \u221A | |
| Python | \u221A | |
| UTF-8 bytes | E2 88 9A | |
| UTF-16 | 221A | |
| URL-encoded | %E2%88%9A |
Character details
| Official name | SQUARE ROOT |
|---|---|
| Unicode block | Mathematical Operators |
| General category | Math Symbol (Sm) |
| SymbolHero category | Math Symbols |
| Emoji | No |
How to type √
Windows
- Hold Alt and type 251 on the numeric keypad (Num Lock on), then release Alt. Alt 251 uses the code page 437.
- In Microsoft Word or Outlook: type
221Athen press Alt + X. - Open Character Map (search “Character Map” in Start), tick “Advanced view”, search for “square root”, then Select and Copy.
Mac
- Press Option + V (US English keyboard layout).
- Press Control + Command + Space to open the Character Viewer, search “square root”, and double-click the result.
- With the Unicode Hex Input keyboard enabled (System Settings → Keyboard → Input Sources), hold Option and type
221A.
iPhone & Android
- Tap Copy at the top of this page, then long-press where you want it and choose Paste.
Docs & web
- Google Docs: Insert → Special characters, then search “square root” or enter
U+221A. - HTML:
√or√ - Excel / Google Sheets:
=UNICHAR(8730)
Examples
- √16 = 4
- √(a² + b²)
- x = (−b ± √(b² − 4ac)) / 2a
Good to know
Don’t mix it up: It is sometimes mistaken for the check mark ✓ (U+2713); the radical has a long horizontal top stroke.
Tip: On Windows, hold Alt and type 251 on the numeric keypad; on a Mac, press Option + V.
Display: the character itself is always the same code point, but its shape comes from the font on the device showing it. If you see an empty box, the font lacks this glyph—the text is still correct.
Similar math symbols
Questions
What is the Unicode for √?
It is U+221A (SQUARE ROOT), decimal 8730.
Is there a Windows Alt code for it?
Yes: Alt 251 on the numeric keypad.
How do I type it on a Mac?
Option + V on a US English keyboard, or use the Character Viewer (Control + Command + Space).
What is the HTML code?
Use the named entity √ or the numeric reference √.