Free Unit Converter Online

The Unit Converter is a free online tool that converts between units of length, weight, temperature, area, volume, speed, and more.

Yes, it is completely free with no registration required. All conversions happen client-side in your browser.

The Unit Converter supports length, weight/mass, temperature, area, volume, speed, and many other measurement categories.

Absolutely. The Unit Converter processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.

Yes, the Unit Converter is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.

No account or registration is needed. Simply open the Unit Converter in your browser and start using it immediately. There are no sign-up walls or usage restrictions.

The Unit Converter uses industry-standard formulas and algorithms to ensure accurate results. However, for critical financial or medical decisions, always consult a qualified professional.

Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.

The Unit Converter works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.

One mile equals exactly 1.609344 kilometers, so to convert miles to kilometers you multiply the distance by 1.609344. Going the other way, one kilometer is about 0.621371 miles, so you divide kilometers by 1.609344 (or multiply by 0.621371). For quick mental math, a handy approximation is to add about 60 percent: 10 miles is roughly 16 km, and 100 km is roughly 62 miles. The relationship is fixed because the international mile is defined in metric terms, which is why the factor is exact rather than rounded. This is useful when reading a road sign abroad, logging a run, or comparing a car's range. Pick the Length category in the converter, enter your value, and set the from and to units to see the precise figure plus the underlying formula.

To convert Celsius to Fahrenheit, multiply the temperature by 9/5 (1.8) and then add 32: degrees F equals degrees C times 1.8 plus 32. To go from Fahrenheit back to Celsius, reverse the steps — subtract 32 first, then multiply by 5/9. A few fixed points help you sanity-check any result: water freezes at 0 degrees C / 32 degrees F and boils at 100 degrees C / 212 degrees F, and the two scales cross at minus 40, where both read the same number. Note that temperature is not a simple ratio like length or weight, because the scales have different zero points, so you cannot just multiply by a single factor. The Temperature category handles this automatically and also supports Kelvin, Rankine, Delisle, and Newton scales. Enter a value and the converted temperature appears as you type.

The gap comes from two competing definitions of a kilobyte. Drive makers use the decimal system, where 1 KB is 1,000 bytes and 1 GB is 1,000,000,000 bytes. Most operating systems report storage in the binary system, where 1 KiB is 1,024 bytes and 1 GiB is 1,073,741,824 bytes. Because the binary unit is larger, the same number of raw bytes shows a smaller figure on screen — a drive sold as 1 TB displays as roughly 931 GiB, a difference of about 7 percent that grows with capacity. Nothing is missing; it is purely a labeling convention. RAM, by contrast, is almost always quoted in binary. The converter's Data Storage category lets you switch between bytes, KB, MB, GB up to petabytes and shows the binary KiB and MiB variants, so you can see exactly how an advertised size maps to what your computer reports.

There is no single gram-to-cup factor, because grams measure weight while cups measure volume, and the conversion depends on the ingredient's density. A cup of water weighs about 236 grams, but a cup of flour is closer to 120 to 125 grams and a cup of granulated sugar around 200 grams, so you cannot use one number for everything. For accurate baking, the most reliable approach is to weigh ingredients in grams and skip volume entirely. When a recipe mixes systems, this tool helps with the parts that do convert cleanly: use the Volume category to move between cups, tablespoons, teaspoons, milliliters, and US or UK gallons, and the Weight category to switch grams, ounces, and pounds. Enter your value, pick the units, and read the result instantly, then apply the right density only where weight meets volume.

A knot is one nautical mile per hour, used in sea and air navigation, while miles per hour measures statute miles per hour, the speed unit on most road signs in the US and UK. The two differ because a nautical mile (1,852 meters) is longer than a statute mile (1,609.344 meters). As a result, one knot equals about 1.15078 mph, so a ship doing 20 knots is moving roughly 23 mph. Knots persist in maritime and aviation use because a nautical mile corresponds neatly to one minute of latitude, which simplifies chart work. To convert in either direction, multiply knots by 1.15078 for mph, or divide mph by 1.15078 for knots. Open the Speed category in the converter, which also covers km/h, meters per second, Mach, and the speed of light, then enter your value to see the exact conversion.