๐ Length Converter
Convert length units in real time โ from millimeters and kilometers to inches and feet. Handy for DIY projects, checking sizes on overseas shopping sites, or estimating distances while traveling. Type a value into any unit field and every other unit updates instantly.
How to use
- Enter a value into any length unit field (mm, cm, m, km, in, ft, yd, mi, etc.).
- The other unit fields update with the converted value in real time.
- To convert a different value, just overwrite the number โ the results recalculate automatically.
How the calculation works
Every length is first converted to metres, then divided back into the target unit. One inch is 0.0254m, a foot 0.3048m, a yard 0.9144m and a mile 1,609.344m. These imperial values are exact definitions, not approximations. The 1959 international yard and pound agreement between the United States, the United Kingdom and others fixed the yard at exactly 0.9144m. That is why an inch comes out at a clean 2.54cm, and why the foot (12 inches) and the mile (1,760 yards) follow exactly from the same definition. For heights given in feet and inches, divide centimetres by 2.54 to get inches, then carry every 12 inches over into a foot.
Worked example
Expressing 170cm in feet and inches 1. To inches: 170 รท 2.54 โ 66.93 2. Divide by 12: 66.93 รท 12 = 5 remainder 6.93 3. Result: about 5 ft 7 in (5โฒ7โณ) A marathon's 42.195km is 42,195 รท 1,609.344 โ 26.22 miles.
Things to be aware of
- The mile here is the statute mile (1,609.344m), not the nautical mile (1,852m).
- The US survey foot, once used in land surveying, differs very slightly, but the international foot (0.3048m) is right for everyday use.
- Displayed values are rounded. For precise machining dimensions, recompute from the defined values.
- Traditional Japanese length units such as shaku and sun have their own converter.
FAQ
Does it support both metric and imperial units?
Yes. Convert freely between metric units (millimeters, centimeters, meters, kilometers) and imperial units (inches, feet, miles).
How precise are the results?
Conversions update in real time and preserve decimal precision based on your input.
Can I convert my height from cm to feet and inches?
Yes โ enter your height in the cm field and it converts automatically to feet/inches, handy for reading foreign height formats.
Is this useful for DIY measurements?
Yes โ quickly convert between mm, cm, and m, which helps when working with imported tools or materials specified in inches.
What if I make a typo?
Just overwrite the number โ every other unit recalculates automatically. There's no separate reset step needed.