What is 21 millimeters to inches? The answer is that 21 mm equals 0.8267 inches.
How to convert 21 mm to inches? We know that one inch is equal to 25.4 millimeters. Therefore, to convert 21 millimeters to inches, we divide the millimeter value by 25.4. This gives us 21 mm ÷ 25.4 = 0.8267 inches. So, 21 mm is equal to 0.8267 inches.
See also: How to convert 21 inches to mm.