Summary: Convert Length Units Free, Without Uploading Anything
A length converter turns a distance in one unit into another unit, such as meters to feet or kilometers to miles. This one covers 12 units, from nanometers to light years, and updates as you type. A second panel, All Conversions, shows the same length in the other 11 units at once.
Nothing you type leaves your device: the conversion runs in your browser, and the Network tab in DevTools shows no request carrying your value. The method is one line: result = value × (length of the source unit in meters) ÷ (length of the target unit in meters). These are the exact definitions it uses:
- 1 inch = 0.0254 m (exactly 2.54 cm), 1 foot = 0.3048 m, 1 yard = 0.9144 m
- 1 mile = 1,609.344 m, 1 nautical mile = 1,852 m
- 1 light year = 9,460,730,472,580,800 m
The metric units step by powers of ten: a kilometer is 1,000 meters, a centimeter one hundredth, a millimeter one thousandth, a micrometer one millionth and a nanometer one billionth. Micrometers suit cell sizes and machining tolerances, nanometers suit light wavelengths and chip features, and light years suit stars and galaxies.
Table of Use: Common Length Conversions
| Task | What you enter | Result shown |
|---|---|---|
| Meters to feet | 1, From Meter, To Foot | 3.280839895013 ft |
| Inches to centimeters | 1, From Inch, To Centimeter | 2.54 cm |
| Height in feet to centimeters | 6, From Foot, To Centimeter | 182.88 cm |
| Kilometers to miles | 1, From Kilometer, To Mile | 0.6213711922373 mi |
| Miles to feet | 1, From Mile, To Foot | 5,280 ft |
| Nautical miles to kilometers | 1, From Nautical Mile, To Kilometer | 1.852 km |
| Millimeters to inches | 25.4, From Millimeter, To Inch | 1 in |
| Light years to miles | 1, From Light Year, To Mile | 5,878,625,373,184 mi |
Features
- 12 units: kilometer, meter, centimeter, millimeter, micrometer, nanometer, mile, yard, foot, inch, nautical mile and light year.
- All Conversions panel with your value in every other unit, so one entry answers several questions.
- Swap button to reverse From and To, and six Common Conversions shortcuts that set the units and reset the value to 1.
- Flexible input: decimals, negative numbers and scientific notation such as 1e-9 are accepted; commas and spaces are ignored.
- Copy button that copies a line such as "1 m = 3.280839895013 ft".
- Clear limits: up to 13 significant digits, scientific notation below 0.000001 or from 1e15 upward, and a message when a value is too large.
How to Use the Length Converter
- Type the number into Value.
- Pick the unit you have in From and the unit you want in To.
- Read the blue result box, and press the copy icon to copy it.
- Press the swap button to reverse the conversion, or scan All Conversions for other units.
- For a quick check, click one of the Common Conversions, such as 1 inch = 2.54 cm.
Who Can Use It
Home builders and DIY users can move between inches, feet, millimeters and centimeters. Travelers can turn kilometers into miles, sailors and pilots can work in nautical miles, students can practice metric prefixes, and lab or electronics readers can use micrometers and nanometers.
For other measurements, use the unit converter, the weight converter or the temperature converter. Once you have a length in the right unit, the area calculator and volume calculator turn dimensions into square and cubic measures, the speed calculator relates distance to time, and the fuel cost calculator prices a trip. Very large or small values are easier to check in the scientific calculator, and the full list lives in the calculators and converters section.
FAQs
How many feet are in a meter?
One meter is about 3.280839895013 feet, which is exactly 1 ÷ 0.3048 because the foot is defined as 0.3048 meters. It is also 39.37007874016 inches. In the other direction, one foot is exactly 0.3048 meters or 30.48 centimeters. Choose Meter in From and Foot in To to see the result.
How do I convert inches to centimeters?
Multiply the inches by 2.54. The inch has been defined as exactly 2.54 centimeters since the 1959 international yard and pound agreement, so 12 inches is 30.48 cm and 6 feet (72 inches) is 182.88 cm. In the converter, choose Inch in From, Centimeter in To and type the value.
How do I convert meters or centimeters to feet and inches?
The converter shows decimal feet or decimal inches, not both at once. Convert to feet, keep the whole number, then multiply the remaining decimal by 12 to get inches. For 1.75 m the tool shows 5.741469816273 ft, which is 5 ft and about 8.9 in. Converting straight to inches gives 68.89763779528 in.
What is the difference between a nautical mile and a regular mile?
A statute mile is exactly 1,609.344 meters. A nautical mile is exactly 1,852 meters, about 15% longer, and is used in aviation and at sea because it was originally based on one minute of latitude. So 1 nautical mile is 1.852 km, or about 1.1508 statute miles.
How long is a light year?
A light year is the distance light travels in a vacuum in one Julian year of 365.25 days: exactly 9,460,730,472,580,800 meters. That is roughly 9.46 trillion kilometers or 5.88 trillion miles; the converter shows 5,878,625,373,184 miles. A light year measures distance, not time.
How accurate is this length converter?
The conversion factors are exact definitions, and results show at most 13 significant digits, the most a standard number can carry through one multiplication and one division with every digit correct. Very small or very large results switch to scientific notation, for example 1e-9 for one billionth of a meter.
Is my value sent to a server when I convert?
No. The conversion is one multiplication and one division done in your browser, so nothing is uploaded. Open the Network tab in DevTools while you type to confirm that no request carries your value. The copy button writes only to your own clipboard.