90 Degrees Calculator

This 90 degrees calculator helps you calculate angles, sides, and areas of right triangles. Whether you're a student studying geometry or a professional working with construction, this tool provides quick and accurate results with visual charts.

What is 90 Degrees?

90 degrees is a right angle, which is exactly half of a straight angle (180 degrees). A right angle forms a perfect L-shape and is fundamental in geometry, trigonometry, and many practical applications.

In a right triangle, the side opposite the right angle is called the hypotenuse, and the other two sides are called legs. The Pythagorean theorem relates these sides: a² + b² = c², where c is the hypotenuse.

Key properties of 90 degrees:

Forms a right angle (90°)
Creates a perfect L-shape
Fundamental in right triangle calculations
Used in construction, navigation, and engineering

Right Triangle Formulas

There are several important formulas for working with right triangles:

Pythagorean Theorem

a² + b² = c²

Where:

a and b are the lengths of the legs
c is the length of the hypotenuse

Area of a Right Triangle

Area = (a × b) / 2

Where:

a and b are the lengths of the legs

Trigonometric Ratios

sin(θ) = opposite/hypotenuse
cos(θ) = adjacent/hypotenuse
tan(θ) = opposite/adjacent

How to Use This Calculator

Using our 90 degrees calculator is simple:

Enter the known values for two sides or one side and one angle
Select the units (inches, centimeters, etc.)
Click "Calculate" to get the results
View the calculated values and chart visualization
Use the "Reset" button to clear the form

Tip: For best results, enter at least two known values to get the most accurate calculations.

Examples

Here are some example calculations using our 90 degrees calculator:

Example 1: Find the Hypotenuse

Given legs of 3 units and 4 units, the hypotenuse is calculated as:

√(3² + 4²) = √(9 + 16) = √25 = 5 units

Example 2: Find the Area

Given legs of 5 units and 12 units, the area is:

(5 × 12) / 2 = 30 square units

Example 3: Find a Missing Leg

Given one leg of 7 units and hypotenuse of 25 units, the other leg is:

√(25² - 7²) = √(625 - 49) = √576 = 24 units

FAQ

What is the difference between a right angle and an obtuse angle?: A right angle is exactly 90 degrees, while an obtuse angle is greater than 90 degrees but less than 180 degrees.
Can I use this calculator for non-right triangles?: No, this calculator is specifically designed for right triangles with one 90-degree angle.
What units should I use for my calculations?: You can use any consistent unit system (inches, centimeters, meters, etc.) as long as all inputs use the same unit.
How accurate are the calculations?: The calculator uses standard mathematical formulas and provides results with up to 4 decimal places for precision.
Can I save my calculations for later?: Currently, the calculator does not have save functionality. You can manually note down your results.