Length units calculator & converter tool
Conversions Table
Equivalent of 18 Inch: |
457.19975311213 Millimeter |
45.719975311213 Centimeter |
0.45719975311213 Meter |
0.00045719975311213 Kilometer |
1.5000723899609 Foot |
0.00028409066779104 Mile |
0.50017652990467 Yard |
0.00024688786668055 Nautical Mile |
Inch / Foot Units Definition
Inch
The inch (symbol: ″ (double prime) or po in French-speaking Canada) is a unit of length dating back to the Middle Ages.Its dimensional value has varied over time, across regions and across countries.Since 1959, following an English compromise, the English inch — also called the “international technical inch” — has been exactly 2.54 cm, or one twelfth of a foot or one thirty-sixth (1⁄36) of a yard. For historical reasons, other definitions of the inch are still in force in certain areas.
Foot
The foot is a unit of length of approximately 30 centimeters, corresponding to the length of a human foot of approximately size 45.In Antiquity, the foot was regularly divided into sixteen fingers or four palms. The Roman foot was 29.64 cm.Since the Middle Ages, the foot was also divided by twelve, which gave the inch. The foot of the King of France was 32.48 cm (size 48¾) and the Anglo-Saxon foot is 30.48 cm.