# Triangle area online calculator

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## Try our triangle area calculator

Welcome to the Triangle Area Calculator, where you can easily find the area of a triangle

### Definition of a Triangle

A triangle is a polygon with three sides and three angles. It is one of the fundamental shapes in geometry and is widely used in various mathematical and real-world applications.

### Overview of Different Formulas for Calculating Triangle Area

Calculating the area of a triangle depends on what information you have about the triangle. There are several formulas available to find the triangle area based on different known parameters.

## Basic Formula

One of the simplest and most commonly used formulas to calculate the area of a triangle is the base and height formula.

### Using Base and Height

The basic formula for finding the area of a triangle is:

A = 0.5 * base * height

where "base" represents the length of the triangle's base and "height" represents the perpendicular distance from the base to the opposite vertex.

## Heron's Formula

When you know the lengths of all three sides of a triangle, you can use Heron's formula to calculate its area.

### Using Three Sides

Heron's formula states:

A = √(s(s - a)(s - b)(s - c))

where "a," "b," and "c" are the lengths of the triangle's sides, and "s" is the semiperimeter, given by:

s = (a + b + c) / 2

This formula is particularly useful when the lengths of all three sides are known.

## SAS Formula

The SAS formula allows you to calculate the area of a triangle when you know the lengths of two sides and the angle between them.

### Using Two Sides and the Angle Between Them

The SAS formula is given by:

A = 0.5 * a * b * sin(C)

where "a" and "b" represent the lengths of the two sides, and "C" is the angle between them. The "sin" function denotes the sine of the angle.

## ASA Formula

If you have information about two angles and a side between them, you can use the ASA formula to find the area of the triangle.

### A. Using Two Angles and a Side Between Them

The ASA formula can be expressed as:

A = 0.5 * a * b * sin(C)

where "a" and "b" represent the lengths of the two sides, and "C" is the angle between them.

## Equilateral Triangle Formula

An equilateral triangle is a special type of triangle where all three sides are of equal length. We have specific formulas to calculate its area.

### Using a² × √3 / 4

For an equilateral triangle, the area formula is:

area = a² × √3 / 4

where "a" represents the length of each side of the equilateral triangle.

### Approximate Formula

If you need a quick approximation of the equilateral triangle's area, you can use the formula:

area ≈ a² × 0.433

## AAA Formula

In some cases, you might have information about all three angles of a triangle. The AAA formula allows you to find the area based solely on the angles.

### Using Three Angles

The AAA formula is not specific since knowing only the angles does not provide sufficient information to determine the triangle's size. Therefore, this method cannot accurately calculate the area of the triangle.

## Conclusion

In conclusion, there are various formulas available to calculate the area of a triangle, depending on the given information. Let's summarize the different formulas we discussed:

### Summary of Different Formulas

• Basic formula: A = 0.5 * base * height
• Heron's formula: A = √(s(s - a)(s - b)(s - c))
• SAS formula: A = 0.5 * a * b * sin(C)
• ASA formula: A = 0.5 * a * b * sin(C)
• Equilateral triangle formula: area = a² × √3 / 4
• Approximate formula for equilateral triangle: area ≈ a² × 0.433
• AAA formula: Not sufficient to determine the triangle's area accurately

### Triangle Area Calculator

If you want to quickly calculate the area of a triangle without manual calculations, you can use our online Triangle Area Calculator. Simply input the known values, and it will provide you with the area instantly.

### Quick Recipe for Approximating Equilateral Triangle Area

For a quick approximation of the area of an equilateral triangle, use the formula area ≈ a² × 0.433. This can come in handy when you need a rough estimate.

Now that you are familiar with the different formulas for calculating triangle area, you can choose the appropriate method based on the available information. Whether it's a basic formula, Heron's formula, or specific formulas for different triangle types, calculating the area of a triangle is now easier than ever.