Square Root Symbol Copy and Paste (√)
Square root (under root)
Unicode U+221A · HTML √ · Alt code Alt+251 · Mac Option+V
Tap any symbol to copy it. Each tap also adds it to the box above, so you can copy several together.
Codes for every symbol on this page (Unicode, HTML, Alt, Mac, Word)
| Symbol | Name | Unicode | HTML | Windows Alt code | Mac | MS Word |
|---|---|---|---|---|---|---|
| √ | Square root (under root) | U+221A | √ | Alt+251 | Option+V | 221A then Alt+X |
| ∛ | Cube root | U+221B | ∛ | - | - | 221B then Alt+X |
| ∜ | Fourth root | U+221C | ∜ | - | - | 221C then Alt+X |
| ² | Square (power 2) | U+00B2 | ² | Alt+253, Alt+0178 | - | 00B2 then Alt+X |
| ³ | Cube (power 3) | U+00B3 | ³ | Alt+0179 | - | 00B3 then Alt+X |
The square root symbol is √, also called the radical sign or simply the root symbol. Writing √49 = 7 means "the number which, multiplied by itself, gives 49 is 7". In Indian classrooms it is often read as "under root", so √2 is "under root 2" or "root over 2".
Tap the big box for a quick root symbol copy, or use the grid for the cube root ∛, fourth root ∜, and the square symbol ² and cube symbol ³ used in m² and cm³. Below you will find shortcuts for Windows, Mac, Word, Excel and phones, examples you can check in your notebook, and the difference between roots and powers. More signs are on the maths symbols hub.
What the Under Root Symbol Means
Squaring and square roots are opposite steps. 7² = 7 × 7 = 49, so √49 = 7. The symbol of square root asks you to undo the squaring.
| Number | Square root | Because |
|---|---|---|
| √1 | 1 | 1 × 1 = 1 |
| √16 | 4 | 4 × 4 = 16 |
| √81 | 9 | 9 × 9 = 81 |
| √144 | 12 | 12 × 12 = 144 |
| √0.25 | 0.5 | 0.5 × 0.5 = 0.25 |
| √2 | about 1.414 | Not a whole number; the decimal goes on forever |
The line on top of the sign, called the vinculum, shows how much is inside the root. √(9 + 16) means add first: √25 = 5. That is different from √9 + √16 = 3 + 4 = 7.
Cube root and fourth root
A small number in the tick of the sign, called the index, tells you which root to take. The cube root symbol ∛ asks which number multiplied three times gives the answer: ∛27 = 3, because 3 × 3 × 3 = 27. The fourth root ∜ works the same way: ∜16 = 2, because 2 × 2 × 2 × 2 = 16. A plain √ with no index always means square root.
Square Root Symbol on Keyboard
| Where | How to type √ |
|---|---|
| Windows | Num Lock on, hold Alt, type 251 on the number pad. This comes from the DOS table and works in most apps. |
| Mac | Option+V |
| Microsoft Word | Type 221A, press Alt+X |
| Google Docs | Insert > Special characters, search "square root" |
| HTML / LaTeX | √ / \sqrt{x}, and \sqrt[3]{x} for a cube root |
∛ and ∜ have no standard Alt code. Use their Word codes, 221B and 221C, followed by Alt+X, or copy them from the grid.
Square root symbol on keyboard phone
On many Android keyboards, including Gboard, tap ?123 and then =\<; the √ sign is on that page. The iPhone keyboard does not show √, so copy it from this page. A handy trick on both phones is to add a text shortcut: for example, set "sqrt" to change into √ in your keyboard's text replacement or personal dictionary settings.
Square Symbol ² and Cube Symbol ³
Powers are the other side of roots. The square symbol ² and cube symbol ³ are small raised digits, called superscripts.
- ²: Alt+0178 (or Alt+253). Used in m², cm², km², and x².
- ³: Alt+0179. Used in m³, cm³ and x³.
For any other power, such as x⁵ or 10⁶, use superscript formatting: in Word press Ctrl+Shift+=, then type the number; in Google Docs press Ctrl+.. Where formatting is not possible, like a plain text message, people use the caret ^ as the power symbol or exponent symbol: x^2 means x squared and 2^10 means 2 to the power 10. See the caret symbol page for more.
A quick reminder of how the two ideas fit together: 5² = 25 and √25 = 5; 4³ = 64 and ∛64 = 4.
Square Root in Excel and Word
Excel and Google Sheets
=SQRT(A2)gives the square root of the number in A2.=SQRT(196)returns 14.=A2^0.5also gives the square root, because a power of one half is a square root.=125^(1/3)gives the cube root, 5. Keep the brackets around 1/3.=A2^2or=POWER(A2,2)squares a number.- To show √ as text in a cell, use Alt+251 or
=UNICHAR(8730).
=SQRT(-4) shows the #NUM! error, because a negative number has no real square root.
Word
To insert the square root symbol in Word so that the bar stretches over the whole number, use an equation: Insert > Equation, then type \sqrt and a space, and type the number inside the box. For a quick single sign in a sentence, the 221A Alt+X method is faster.
Worked Examples with Roots
- Simplify √50. 50 = 25 × 2, so √50 = √25 × √2 = 5√2, which is about 7.07.
- Find the side of a square. A square plot has area 169 m². Side = √169 = 13 m.
- Pythagoras. A right triangle has sides 6 cm and 8 cm. The longest side = √(6² + 8²) = √(36 + 64) = √100 = 10 cm.
- Estimate a root. √30 is between √25 = 5 and √36 = 6, and closer to 5, so √30 ≈ 5.5. (A calculator gives 5.477.)
Remember that the equation x² = 25 has two answers, x = ±5. The √ sign alone gives only the positive root, √25 = 5. The plus minus symbol page explains ± in more detail.
Common Mistakes
- Using a tick mark: ✓ and √ look a little alike, but the tick is a different character. If you need a check mark, use the tick symbol page.
- Splitting a sum: √(a + b) is not √a + √b. Check with numbers: √(9 + 16) = 5, not 7.
- Writing m2 instead of m²: in reports and forms, use the proper square symbol so the unit reads correctly.
Frequently asked questions
How do I type the square root symbol on keyboard?
On Windows, hold Alt and type 251 on the number pad with Num Lock on. On a Mac, press Option+V. In Word, type 221A and press Alt+X.
What is the symbol of root called?
√ is called the radical sign. In everyday use it is called the square root symbol or under root symbol.
How do I type the cube root symbol?
There is no standard Alt code for ∛. In Word, type 221B and press Alt+X, or copy ∛ from the grid on this page.
What is the power symbol on a keyboard?
The caret ^ (Shift+6) is used as the power symbol in plain text, Excel and calculators: 3^2 means 3 squared. For neat writing, use superscripts like ² and ³.
How do I find a square root in Excel?
Use =SQRT(number), for example =SQRT(81) gives 9. You can also raise a number to the power 0.5, as in =81^0.5.
What does under root 2 mean?
"Under root 2" is how many Indian students read √2. It is the number that, multiplied by itself, gives 2, which is about 1.414.