
Here is how to convert 521.5 mm to inches. We will give you the fractional answer, the decimal answer, and illustrate the answer on our tape measure.
One millimeter is equal to 5/127 inches, and 521.5 as a fraction is 1043/2. Therefore, to get the fractional answer to 521.5 mm in inches, we multiply 1043/2 by 5/127 and simplify if necessary.
cm × 5/127 = inches
1043/2 × 5/127 = inches
1043/2 × 5/127 = 20 135/254
1043/2 mm = 20 135/254 inches
521.5 mm = 20 135/254 inches
As promised above, we also have the answer to 521.5 mm in inches in decimal form. Although the fractional answer above is exact, the decimal answer may be rounded if necessary:
20 135/254 ≈ 20.5314960629921
20 135/254 ≈ 20.53150
521.5 mm ≈ 20.53150 inches
Our image below shows 521.5 mm on a tape measure. The top row of the tape measure is inches, and each mark on the bottom row is 1 millimeter (10 millimeter marks equal 1 centimeter).

As you can see, we drew a red line where 521.5 mm and 20.53150 inches meet on the measuring tape.
Millimeters to Inches Calculator
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