SQRT Function in Excel: Square Root

📎 This article includes 1 downloadable practice file ↓

MathLevel: BeginnerAvailable in: Excel 2007+

In this article

1. Syntax
2. Examples
3. Example 1
4. Example 2
5. Common errors and fixes
6. SQRT in practice
7. Where you will use it
8. Worked example
9. Mistakes people make
10. Related functions
11. Continue learning

SQRT returns the positive square root.

Syntax

=SQRT(number)

Argument	What it means
number	Zero or positive.

Examples

Example 1

=SQRT(A2^2+B2^2)

Straight-line distance from x/y differences.

Example 2

=STDEV.S(B2:B253)*SQRT(252)

Annualise daily volatility (252 trading days).

Common errors and fixes

You see	Why, and the fix
#NUM!	Negative number. Use ABS if appropriate.

SQRT in practice

Where you will use it

• Standard deviation steps and statistics
• Side length from an area
• Distance calculations

Worked example

Value	Formula	Result
144	=ROUND(SQRT(A2),4)	12
2	=ROUND(SQRT(A3),4)	1.4142
1000000	=ROUND(SQRT(A4),4)	1000

Results calculated in Excel.

Mistakes people make

Mistake	What to do instead
Negative numbers	SQRT(-1) is #NUM!; use ABS if appropriate
Higher roots	Use A2^(1/3) for cube roots

Related functions

POWER · ABS

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📎 Practice files for this article

• 📗
  Practice workbook: Math & rounding24 tasks on realistic sales data — type your formula, the Check column turns green when it is right. Answers sheet included.
  ⬇ XLSX · 35 KB

Free to use for learning. Files with macros (.bas) are plain text — import them with Alt+F11 → File → Import File, and always test on a copy.