How to Type the Square Root Symbol (√) on Any Device

The square root symbol √ — formally called a radical sign — is a mathematical symbol used to denote the square root of a number. Whether you’re writing a math tutorial, formatting an equation in a document, or building a calculator app, this guide covers every way to type or insert √ on any device.

What Is the Square Root Symbol?

The square root symbol √ is known in mathematics as the radical sign. It was first used in print in 1525 by German mathematician Christoph Rudolff, and its shape is believed to have evolved from the lowercase letter “r” (for the Latin word radix, meaning root).

Its Unicode code point is U+221A, and it has been part of the Unicode Standard since version 1.0. The symbol appears in three common forms:

• √ — Square root (U+221A)
• ∛ — Cube root (U+221B)
• ∜ — Fourth root (U+221C)

How to Type the Square Root Symbol on Windows

Method 1: Copy and Paste

The quickest method on any device — copy √ directly from this page and paste it wherever you need it. Works in every browser, app, and text editor.

Method 2: Alt Code

1. Make sure Num Lock is on
2. Hold down Alt
3. Type 251 on the numeric keypad
4. Release Alt — √ will appear

Method 3: Unicode Input (Microsoft Word)

1. Type 221A
2. Immediately press Alt + X
3. Word converts it to √

Method 4: Character Map

Open the Windows Character Map (Start > search “Character Map”), search for “square root” or scroll to U+221A, click Copy, then paste it into your document.

Method 5: Windows Emoji Panel

Press Windows key + . (period) to open the emoji/symbol panel, go to the Symbols tab, and search for “square root.”

How to Type the Square Root Symbol on Mac

Method 1: Keyboard Shortcut

Mac has a direct keyboard shortcut for the square root symbol:

Press Option + V

That’s it — √ will be inserted instantly. This is the fastest method on macOS.

Method 2: Character Viewer

1. Press Control + Command + Space
2. Search for “square root” or “radical”
3. Double-click √ to insert it

Method 3: Unicode Hex Input

Enable Unicode Hex Input under System Settings > Keyboard > Input Sources. Then hold Option and type 221A to produce √.

How to Type the Square Root Symbol on iPhone and Android

Mobile keyboards don’t include √ by default, but there are a few reliable workarounds:

iPhone (iOS)

1. Go to Settings > General > Keyboard > Text Replacement
2. Tap the + button
3. In Phrase, paste √
4. In Shortcut, type something like sqrt

From then on, typing sqrt will auto-suggest √ as a replacement.

Android

In Gboard, go to Settings > Dictionary > Personal Dictionary and add √ as a word with a shortcut like sqrt. Alternatively, many Android keyboards have a symbols or math keyboard accessible by holding the ?123 key.

Square Root Symbol in HTML, CSS, and Code

For developers and web publishers, here are the correct ways to render √ in code:

Method	Code
HTML entity	√ or √
HTML named entity	√
CSS content property	content: "\221A";
Direct UTF-8	√ (works in any UTF-8 encoded file)
LaTeX	\sqrt{}
HTML math (MathML)	<msqrt> tag

Note for developers: For rendering proper math equations on the web, consider using MathJax or KaTeX instead of the raw Unicode character. These libraries render publication-quality math and properly extend the radical sign bar over the expression.

Square Root Symbol in Microsoft Word and Google Docs

Microsoft Word

Beyond the Alt+X method, Word has a built-in equation editor:

1. Go to Insert > Equation
2. Select Square Root from the math structures menu
3. This renders a full radical sign with the overbar extending over your expression — ideal for formal documents

Google Docs

1. Go to Insert > Special Characters
2. Search for “square root”
3. Click √ to insert it

For proper equations in Google Docs, use Insert > Equation which supports LaTeX-style input — type \sqrt followed by Space to trigger the radical structure.

Related Math Symbols You May Need

Symbol	Name	Unicode	Alt Code (Windows)	Mac Shortcut
√	Square root	U+221A	Alt + 251	Option + V
∛	Cube root	U+221B	—	—
∜	Fourth root	U+221C	—	—
²	Superscript 2	U+00B2	Alt + 253	—
³	Superscript 3	U+00B3	Alt + 0179	—
π	Pi	U+03C0	Alt + 227	—
∞	Infinity	U+221E	Alt + 236	—
±	Plus or minus	U+00B1	Alt + 241	Option + Shift + =

Quick Reference: Square Root Symbol Cheat Sheet

Symbol	√
Name	Radical sign
Unicode	U+221A
HTML entity	√ or √
Windows Alt code	Alt + 251 (numpad)
Windows (Word)	Type 221A then press Alt+X
Mac shortcut	Option + V
Mobile	Copy/paste, or set a text replacement shortcut
LaTeX	\sqrt{}
Unicode since	Version 1.0

Final Thoughts

The square root symbol √ is one of the more accessible math symbols to type — Mac users have the luxury of a direct Option + V shortcut, while Windows users can rely on the Alt + 251 numpad code or the Alt + X method in Word. For developers, the named HTML entity √ is clean and universally supported. And if you’re working with complex equations in a document or on the web, the equation editors in Word, Google Docs, MathJax, or KaTeX will give you far more control over how the radical sign renders.