Hypotenuse Calculator

Pythagorean Theorem for calculating the hypotenuse

Calculating the hypotenuse of a triangle is very easy thanks to the Pythagorean Theorem. This theorem says that the hypotenuse is equal to the square root of the sum of the legs squared, therefore, knowing this data, we can find out the value of the hypotenuse.

With our hypotenuse calculator online you can directly apply the Pythagorean Theorem, but if you need to know the value of the other legs, we also have another way to apply it. calculator to solve triangles.

Pythagorean Theorem for calculating the hypotenuse

What is the hypotenuse of a triangle?

The hypotenuse is the longest side which has a right triangle and also corresponds to the side opposite the right angle (the 90º side).

In the image above, it would correspond to leg C of the triangle.

How do you calculate the hypotenuse of a triangle?

Pythagorean Theorem for calculating the hypotenuse

As we have commented at the beginning, to calculate the hypotenuse of a triangle knowing the measure of the two legs we have to use the Pythagorean Theorem.

Este teorema enuncia que "el cuadrado de la hipotenusa es igual a la suma del cuadrado de los catetos", por lo tanto, para calcular la hipotenusa debemos apply the following formula mathematics:

c = √(a2 + b2)

By example,Let's imagine that we have a triangle whose legs measure 2 cm and 5 centimeters respectively. Applying the previous expression we have that its hypotenuse measures:

c=√(22 + 52) = √(4 + 25) = √29 = 5.39 centimeters

As you can see, calculating this side of the triangle does not involve more difficulty than to clear the unknown in a proper way and solve the operation correctly. To do this, we we recommend that you follow these steps:

  1. Square the length of each cathetum
  2. Add the values obtained from the previous step
  3. Apply the square root to the result of step two.

If you follow this orderly methodology, there is very little chance of getting it wrong and if you have doubts about whether you have done it right, you can always use our calculator to compare the result you have obtained and that of our tool. If they match, congratulations!

Of course, you can use this formula for all triangles that are right angles, so it doesn't matter if it is isosceles, equilateral or any other as long as there is an angle of 90 degrees.

Calculate legs knowing the hypotenuse

Pythagorean Theorem Calculator

If we are asked to Calculate the legs of the triangle knowing the hypotenuse. and we are not given any other data, then we automatically know that it is an isosceles triangle and, therefore, it has two equal sides. This means that the formula of the Pythagorean Theorem applied to this example will be as follows:

c2 = a2 + a2 = 2a2

El valor de 'c' será la hipotenusa y el de 'a' el de los catetos que tenemos que calcular. Ahora tenemos que despejar de la fórmula anterior el valor de a:

a = c/√2

That is, if we have to to find the value of the legs of a triangle from the hypotenuse we will have to divide it by the square root of two.

Calculate hypotenuse with cathetus and angle

Triangle to calculate trigonometric ratios

We can also calculate the hypotenuse of a triangle if we are given one of the legs and the angle. Here is the formula for the two possible cases.

If we are given the angle and the opposite cathetus, we can calculate it with this formula:

h = opposite cathetus / sin(θ)

In the case that we are given the adjacent leg and the angle, the formula we will use will be this other one:

h = adjacent cathetus / cos(θ)

For example, let's find the hypotenuse of a triangle of which we know that it has an angle of 30º and its opposite leg measures 20 cm. To solve it, we use the first formula and solve:

h = opposite / sin(θ) = 20 cm / sin(30) = 20 cm x 0.5 = 10 cm

Easy, isn't it? If you have any doubt or problem regarding the calculation of the hypotenuse, leave us a comment and we will help you as soon as possible.

Hypotenuse of a square

There is no hypotenuse in a squareor at least that's not the right way to name it. Actually, what you are looking for is how to calculate the diagonal of a square and in the link we have just left you will find all the details to do so.

Cómo funciona la calculadora de hipotenusa online

Pythagorean Theorem for calculating the hypotenuse

Si estás buscando cómo calcular la hipotenusa de un triángulo online, nuestra calculadora te facilitará el cálculo y obtendrás el resultado de forma rápida y sencilla, algo perfecto si quieres ahorrarte operaciones o quieres comprobar los resultados de algún ejercicio.

Para sacar la hipotenusa de cualquier triángulo rectángulo sabiendo las longitudes de sus catetos a y b. Solo tienes que introducir las dimensiones de cada lado en la casilla que corresponda y pulsar el botón de calcular para obtener el resultado.

Es importante que los dos catetos tengan las mismas unidades para que el resultado final sea correcto. Es decir, si el cateto a está expresado en centímetros, el cateto b también debe estarlo. Por lo tanto, la hipotenusa también estará expresada en centímetros.

De todas formas si tienes dudas con algún ejercicio de calcular la hipotenusa, déjanos un comentario con el enunciado del problema y te ayudaremos a resolverlo.

16 thoughts on “Calculadora de hipotenusa”

    • Hello Ingrid,

      You can calculate it here:

      Just apply the formula at the end of the article, which will give you a height of 8.66 centimeters.


    • Hoola Macarena,

      If you notice, the formula to calculate the hypotenuse of a triangle from the opposite angle is this:

      h = opposite cathetus / sin(θ)

      In the statement we are told that the opposite leg is 20 centimeters and the angle is 30º. If we calculate the sine of 30º, the result is 0.5.

      Therefore, we multiply 20 x 0.5.


  1. If I have the hypotenuse and the adjacent leg, what is the formula to calculate the opposite leg? H= 192, A=168 B=?
    I would like to calculate how much is B I try to do the inverted formula but I am missing an ingredient. Thanks for your help

    • Hello Elias,

      To solve the exercise you are asking us to do we have to use the Pythagorean Theorem.

      With the data you give us, leg B would measure 92.95 cm.

      If you want to learn how we have solved the exercises, click on the link we have left you and if you have any doubts, ask us with complete confidence.


    • Hello Juan,

      Your problem is very easy to solve. We explain it to you below:

      h = √(a2 + b2) = √(1 + 1) = √2 = 1,41 cm

      Since the two legs are equal and of value 1, the value of the hypotenuse is obtained by calculating the square root of 2.

  2. hello could you help me to find the cathetus of a scalene triangle, I have the value of the hypotenuse which is 1,52

    • Good morning Daniela:

      It is impossible to find both legs if we only know the hypotenuse, we should know at least two pieces of information.


  3. Hello, I want to know what is the length of the hypotenuse of a triangle whose legs measure 2cm and 3cm, and if the length of the legs is 3cm and 4cm?

    • Hello Aracelys,

      In the first case the hypotenuse would be 3.61cm and in the second case it goes up to 5cm.

      Remember that you have the calculator to do it yourself immediately with the values you want.

  4. Hola disculpa será que me puedes ayudar con un ejercicio,
    El cateto opuesto del triángulo mide 6 y el ángulo es de 10 grados, no tengo la medida de la hipotenusa ni el cateto adyacente

  5. Hola, excelente post! Muchas gracias por la información.

    Si conozco la hipotenusa (3,4) y el ángulo entre hipotenusa y adyacente (30°)


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