Square root in code
Unicode escapes, HTML entities, LaTeX — and the actual functions that compute a square root in JavaScript, Python, Excel, and half a dozen other languages.
Unicode escapes & HTML entities
√ is Unicode code point U+221A. Most languages let you drop it straight into a string literal using an escape sequence instead of pasting the raw character.
"\u221A" // √"\u221a" # √"\u221A" // √√ or √content: "\221A";LaTeX
\sqrt renders a proper radical with a bar over its argument in LaTeX, MathJax, and KaTeX — add a bracketed number for anything past a square root.
\sqrt{x}\sqrt[3]{x}\sqrt[n]{x}Calculating a square root in code
An escape sequence just gets the symbol onto the page — it doesn't compute anything. Here's the actual function or formula for each language and its result on 25.
Math.sqrt(25);
// 5import math
math.sqrt(25)
# 5.025 ** 0.5
# 5.0=SQRT(A1)Math.sqrt(25);
// 5.0#include <math.h>
sqrt(25);
// 5.0sqrt(25);
// 5SELECT SQRT(25);
-- 525.0.squareRoot()
// 5.0sqrt(25)
# 5Gotchas worth knowing
Negative numbers
Math.sqrt(-1) returns NaN in JavaScript and Java. Python's math.sqrt(-1) raises a ValueError instead of returning anything — wrap it in a try/except if the input might be negative, or use cmath.sqrt() to get a complex result.
Integer vs. float results
Math.sqrt() always returns a float/double, even for perfect squares — Math.sqrt(25) is 5, not an int. In statically typed languages like Java or C, remember to store the result in a double, not an int, or it truncates.
Precision
Floating-point square roots aren't always exact. sqrt(2) ** 2 can come out to 2.0000000000000004 rather than 2 in most languages — round before comparing for equality.
Just need the symbol itself?
The copy formats page has √ ready to paste as plain text, a Unicode code point, an alt code, or a spreadsheet formula — no code editor required.
Open copy formatsFrequently asked questions
What is the Unicode escape for the square root symbol in code?
In JavaScript, Java, and C# string literals, use \u221A (capital A). In Python, use \u221a (lowercase a works the same as uppercase — Python's escape is case-insensitive for the digits, but lowercase is the conventional style). Both resolve to the same character, √, which is Unicode code point U+221A.
How do I calculate a square root in JavaScript?
Use Math.sqrt(x) — for example Math.sqrt(25) returns 5. It returns NaN for negative numbers since JavaScript's Math object doesn't handle complex numbers.
How do I calculate a square root in Python?
Import the math module and call math.sqrt(x), e.g. math.sqrt(25) returns 5.0. You can also use the exponent operator, 25 ** 0.5, which needs no import but returns a float either way. For negative inputs, math.sqrt() raises a ValueError — use cmath.sqrt() if you need a complex result.
What's the Excel or Google Sheets formula for square root?
=SQRT(A1), replacing A1 with the cell or number you want rooted. Both Excel and Google Sheets use identical SQRT() syntax. Pasting the √ character into a cell only displays it — it doesn't compute anything.
What's the LaTeX command for a square root?
\sqrt{x} renders a radical with a bar over x. For a cube root or other nth root, add a bracketed argument: \sqrt[3]{x} for cube root, \sqrt[n]{x} for an arbitrary root. Works in LaTeX, MathJax, and KaTeX.
Why does Math.sqrt(-1) return NaN instead of an error?
JavaScript's Math object only works with real numbers, and the square root of a negative number is imaginary. Rather than throwing, Math.sqrt() returns NaN (Not a Number) so a single bad value doesn't crash a larger calculation — check for it with Number.isNaN() if you need to handle it explicitly.