Content

• To step
• Method 1 of 3: Calculate an area in square meters
• Method 2 of 3: Convert from other units
• Method 3 of 3: Calculate square meters of complex shapes
• Tips
• Necessities

Square meters are a unit of measure of an area, it is usually used to determine the dimensions of a flat surface such as a field or a floor. For example, you can measure the area of ​​a sofa in square meters and then the area of ​​your room so that you know whether the sofa will fit in it. If you only have a tape measure that says "feet" or some other non-metric unit of measure, you can still measure the area with it and then convert it to square meters.

To step

Method 1 of 3: Calculate an area in square meters

1. Choose a folding rule or a tape measure. Take a folding rule or tape measure marked with meters (m) or centimeters (cm). This makes it easiest to calculate square meters, as they fall within the same metric system.
   • If you are in a foreign country, you may only be able to find a tape measure with feet (ft) or inches (in) on it. Then just use it and convert it to square meters later.
2. Measure the length of the surface. Square meters are a unit of measure for measuring an area, or the size of a two-dimensional object such as a floor or field. Use your tape measure or folding rule to measure one side of the object from one corner to the other. Write down the outcome.
   • If the object is longer than 1 meter you have to write down both the meters and the centimeters. For instance 2 meters and 35 centimeters.
   • If you want to measure an area that is not rectangular or square, continue reading the third part of this article on complex shapes.
3. If you can't measure the entire length at once, do it in parts. Put down your tape measure, and then place a rock or other small object in a place that you can easily remember (such as 1 meter and 25 centimeters). Pick up your tape measure again and unroll it, starting from the object you placed. Repeat this until you have had the entire length and add all the measurements together.
4. Measure the width. Use the same tool to measure the width. The side that you are going to measure now must make an angle of 90º with the previously measured side. Also write down this result.
   • Unless the object you are measuring is less than 1 meter, you can round to the nearest centimeter. For example, if the width is slightly more than 1 meter and 8 centimeters, you can just write "1 meter and 8 centimeters", without millimeters.
5. Convert from centimeters to meters. Normally, a measurement will not be accurate to whole meters. That's why you have to write down both the meters and the centimeters. Because 1 meter is 0.01 meter, you can display the measurement in meters by sliding the decimal point two centimeters to the left. Here are some examples:
   • 35cm = 0.35m, so 2m 35cm = 2m + 0.35m = 2.35m
   • 8cm = 0.08m, so 1m = 8cm 1.08m
6. Multiply the length by the width. If you have written both dimensions in meters, you can multiply them to get the area in square meters. Use a calculator for this if necessary. For instance:
   • 2.35mx 1.08m = 2.5272 square feet (m).
7. Round it off to a more convenient size. If you get a lot of digits after the decimal point, for example 2.5272, you probably want to round it to a number with fewer digits, for example 2.53 square meters. Since you probably haven't measured accurate to the millimeter anyway, those last numbers aren't really accurate. In most cases you can just round to the nearest centimeter.
   • If you multiply two numbers with the same unit of measure (for example, meters), the answer is always in the form of a square unit (m², or square meters).

Method 2 of 3: Convert from other units

1. Multiply "square feet" by 0.093. Measure the length and width and multiply them to get "square feet". Since 1 "square feet" equals 0.093 square meters, you have to multiply the result by 0.093 to get the answer in square meters. A square meter is bigger than a square feet, so you need less of it to cover the same area.
   • For greater precision, multiply by 0.092903.
2. Multiply square yards by 0.84. If you measured in square yards, multiply by 0.84 to get square yards.
   • For greater precision, multiply by 0.83613.
3. Multiply acres by 4050. One acre is approximately 4050 square feet. If you want to be even more accurate, multiply by 4046.9.
4. Convert square miles to square kilometers. A "square mile" is much larger than a square meter, so that is normally converted to square kilometers. Multiply the square miles by 2.6 to get the area in square kilometers (or by 2.59 if it needs to be more accurate).
   • If you still want to convert to square meters, 1 square kilometer is 100,000 square meters.
5. Convert square feet to a unit of area, not length. Square meter is a unit of surface, or two-dimensional planes. So it makes no sense to compare this with a unit that length, or measures the distance in one direction. You can convert between "square meters" and "square feet", but not between "square meters" and "feet".
   • Do not use the calculation methods in this section to convert between units of length. You need different numbers for that.

Method 3 of 3: Calculate square meters of complex shapes

1. Divide the mold into pieces. If you need to solve a math problem, draw or cut lines to divide the shape into simpler shapes, such as rectangles and triangles. If you need to measure a room or other physical object, sketch the area first and do the same. Measure each part and write it on the drawing. Follow the instructions below to calculate the area of ​​each part and add the results.
2. Measure rectangular shapes as you normally would. To calculate the area in square footage, see the first part of this article.
   • If you measure in a different unit, see the second part of this article.
3. Measure right triangles the same and divide by two. A right triangle has an angle of 90º, just like the corners of a rectangle, so that area is easy to calculate. Measure the two sides that form a 90º angle (the length and the width), multiply them, then divide by two to find the answer in square meters.
   • This works because a right triangle is exactly the size of a rectangle cut diagonally in half. So you just calculate the area of ​​that rectangle, but then divide it by two to calculate the area of ​​the triangle.
4. First make a right triangle from other triangles and then measure them. Draw a line from one corner of the triangle to the opposite side, so that the line touches the other side at a 90º angle (imagine the angle of a square). Now you have divided the triangle in half, and they are both right triangles! Now refer to the instructions above to learn how to calculate the area of ​​a right triangle; measure both triangles separately and add them together.
5. Calculate the area of ​​a circle. The area of ​​a circle is π x r². r is the radius, which is the distance from the center of the circle to the edge. Measure this distance, multiply it by itself and multiply the result by π (Pi) on a calculator. If you don't have a calculator with a π function, use 3.14 (or 3.1416 if you need to be more accurate).
   • If you don't know exactly what the center of the circle is, have a friend hold a tape measure and walk over the edge of the circle. Hold the other end of the tape measure yourself and change places until you find the spot where the measurement stays exactly the same as your friend walks around the edge of the circle.
   • More complicated curved edges require more complicated math calculations. If you are measuring a room for practical reasons, it may be easier to estimate the area by viewing the curved edges as consecutive straight lines.

Tips

• Say "five square feet" instead of "five feet square." Both are technically correct, but the second is often misinterpreted as an area five meters long and five meters wide (which is also 25 square meters, or 5 x 5).
• If you are not sure whether you have calculated it correctly, you can check whether your answer is a bit correct with the following dimensions:
  • A football field is between 4000 and 9000 square meters.
  • A king-size mattress is approximately 5 square feet.

Necessities

• Ruler or tape measure
• Calculator