Length Converter
Convert between meters, feet, miles, inches, kilometers, and more instantly.
- Free, no account
- No watermark
- No usage limit
About the Length Converter
Most length converters make you commit to two units before they'll tell you anything. You've got meters, you want feet, so you set the "from" to meters, set the "to" to feet, and read your one number. Then you realize you actually wanted yards. Back you go to change the target. This one kills that back-and-forth. Type your value, pick the single unit you're starting from, and every other unit fills in at the same moment, millimeters all the way up through nautical miles, updating live as you type. Nine answers instead of one, so you never have to know which unit you want before you've seen it.
That sounds small until you're mid-task and can't remember whether a spec was written in feet or yards, or whether a room reads better to you in meters or centimeters. Instead of converting, squinting, and converting again, you get the whole column and read the line that helps. Each row has its own copy button, so you grab the exact figure and paste it. And there's a "Copy shareable link" button that packs your value and unit into the web address, so you can hand someone "6 feet, in everything" as a link that opens already filled in.
How to use
- Type your number in the Value box. Whole numbers, decimals, tiny or huge, all fine.
- Pick the unit you're starting from in the From dropdown (inches, meters, miles, whatever you have).
- Read the table. Every supported unit shows your value converted, and it changes the instant you type. No button to press.
- Hit copy on any row to put that single figure on your clipboard.
- Use Copy shareable link to grab a URL that reopens this exact conversion. Good for sending a measurement to someone or bookmarking one you check often.
No sign-up, nothing to install, and it's free. All the math runs in your browser, so it's instant, it keeps working if your connection drops after the page loads, and nothing you type leaves your device.
Seeing every unit at once actually changes how you work
The two-box converters answer a question you have to fully form first: this exact unit, into that exact unit. Honestly, a lot of the time you don't know the target yet because you're still comparing. Is 120 cm closer to 4 feet or to a yard and a bit? With a single-answer tool you'd check feet, then re-pick and check yards. Here both sit on screen already, next to the millimeters and meters and inches, and you decide by looking.
It also catches your own mistakes. If you meant centimeters but picked meters, the whole column comes out a hundred times too big, and that's obvious right away instead of after you've trusted one wrong number.
Best way to use it: pick the unit you actually have in hand, not the one you think you want at the end. The measurement printed on the furniture listing, the number on the pattern, whatever's in front of you. Let the table tell you the rest. Then copy the one line that matters, or share the whole set as a link.
The two units that cause most wrong answers
Nautical miles and feet-and-inches account for more wrong conversions than every metric decimal slip put together.
Nautical miles are not regular miles. The two sit close enough together to look interchangeable, which is exactly what makes the mix-up easy. A nautical mile is exactly 1,852 meters, about 15% longer than a statute mile's 1,609.344 meters. The gap is small over a short distance, but it grows fast across a full flight plan or a long sea route. If you're doing anything with navigation, double-check you grabbed the right "mile," because the two sit one row apart in the table and it's an easy slip.
Feet and inches don't add up like decimals. "5 feet 9 inches" is not 5.9 of any unit, it is 5 feet plus 9 inches, which comes to 69 inches total, or 175.26 cm. Type 5.9 into feet expecting a person's height and you'll get 5 feet plus nine tenths of a foot, which works out to 5 feet 10.8 inches, a different person entirely. Convert the height to one unit first (69 inches), then read it off the table.
One more that almost never matters but people ask about. There are two slightly different "feet." The international foot this tool uses is exactly 0.3048 meters, and it's what everyone means in daily life. A "US survey foot" differs out at the seventh decimal and only ever showed up in old land-survey records. For anything you'd bring to a converter, they're identical.
The factors themselves are exact, not rounded approximations. One inch is defined as 2.54 cm, one mile as 1,609.344 meters, one nautical mile as 1,852 meters. So the answers hold up for real work, and the only rounding is in how many digits fit on screen.
Frequently asked questions
Why does an answer sometimes show as scientific notation?
When a result gets extremely large or extremely small, the tool switches to notation like 1.5e-7 rather than a screenful of zeros. It stays readable and precise at once, so a tiny machining tolerance and a huge travel distance are both legible. For ordinary sizes you'll just see normal digits.
How many decimal places does it keep?
Up to eight significant figures, more than a construction plan or a design layout will ever ask for. If your task wants a cleaner figure, round the displayed number yourself. The tool never rounds early, so nothing gets lost before it reaches you.
What does the shareable link actually contain?
Just your value and the unit you picked, encoded straight into the web address. Open that link and the converter loads already set to that conversion. There's no account and no tracking, the numbers live in the link itself and nowhere on a server.
Can I convert something the table doesn't list?
The nine units here cover almost every real length question, from a screw thread up to the distance between cities. For scientific extremes like micrometers, nanometers, or light years you'd want a specialist tool, since those deliberately aren't on this list.
Does it handle negative numbers or zero?
Zero converts to zero across the board, as you'd expect. A negative length doesn't mean much physically, but if you type one the math still runs consistently through every unit, so you won't hit a crash or a blank cell.
Why is one row shaded differently from the rest?
That highlighted row is the unit you're converting from. It's shaded so your eye can keep its place while running down the column, and its value simply mirrors what you typed in the box.
Is this accurate enough for engineering?
Yes, with margin to spare. Eight significant figures pins a one-meter dimension down to about a tenth of a micron, and even precision machining holds to roughly a ten-thousandth of an inch (about 2.5 microns), some twenty-five times coarser than the tool can resolve. So the conversion itself is never where error creeps in.