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Magnitude of a Vector

This online calculator calculates the magnitude of a vector

This online calculator calculates the magnitude of a vector, either a free vector using its coordinates or a bound vector using coordinates of its initial and terminal points. Some recap theory and formulas can be found below the calculator.

Terminal point coordinates

Digits after the decimal point: 2
Magnitude

The magnitude of a vector

Here we talk about Euclidean vector, which is a geometric object that has magnitude (or length) and direction. Graphically it can be represented as an arrow, connecting an initial point with a terminal point. Such vector is called bound vector. It is defined by initial point and terminal point coordinates. When you care only about the magnitude and the direction of the vector, and not about the particular initial point, such vector is called a free vector. Free vector is equivalent to the bound vector whose initial point is the origin.

The length or magnitude or norm of the vector a is denoted by ‖a‖ or, less commonly, |a|, which is not to be confused with the absolute value (a scalar "norm").

The length of the vector a can be computed with the Euclidean norm

$\left\|\mathbf {a} \right\|={\sqrt {a_{1}^{2}+a_{2}^{2}+a_{3}^{2}}}$
which is a consequence of the Pythagorean theorem since the basis vectors e1, e2, e3 are orthogonal unit vectors.1

In case of three-dimensional space with x, y and z coordinates the formula becomes
$\left\|\mathbf {a} \right\|=\sqrt{x^2+y^2+z^2},$ for free vector
and
$\left\|\mathbf {a} \right\|=\sqrt{(x_1-x_0)^2+(y_1-y_0)^2+(z_1-z_0)^2},$ for bound vector

PLANETCALC, Magnitude of a Vector