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SQRT Function
Summary
The Excel SQRT function calculates the positive square root of a given number. It's a fundamental mathematical function essential for geometric calculations, statistical analysis, and financial modeling where square root operations are required.
Syntax
SQRT(number)Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
| number | Number |
Yes | A non-negative number whose square root you want to calculate |
Using the SQRT Function
SQRT is perfect for calculating distances between points, standard deviations, and various financial ratios. Use it when you need the principal (positive) square root of a value in your spreadsheets.
Common SQRT Examples
Basic Square Root Calculation
=SQRT(16)Returns 4, the positive square root of 16.
Handling Negative Numbers
=SQRT(-16)Returns #NUM! error since negative numbers don't have real square roots.
Safe Negative Number Handling
=SQRT(ABS(-16))Returns 4 by first converting -16 to 16 using ABS function.
Area to Side Length
=SQRT(A1)If A1 contains 25 (area of square), returns 5 (side length).
Frequently Asked Questions
Common Errors and Solutions
#NUM!
Cause: Input number is negative
Solution: Use ABS() function first: =SQRT(ABS(number))
#VALUE!
Cause: Input is not a number (text, etc.)
Solution: Ensure input cell contains numeric value
Notes
- Always returns positive root (principal root)
- For complex square roots use IMSQRT function
- Perfect numbers like 16, 25, 36, 49 have integer square roots
- Combine with ABS for safe negative number handling
Compatibility
Available in: Excel 2007, Excel 2010, Excel 2013, Excel 2016, Excel 2019, Excel 2021, Microsoft 365, Excel for Web
Not available in:
Content last reviewed: December 11, 2025
Update frequency: As needed
Excel versions tested: Excel 2007+