Unit Converter
Convert length, weight, temperature, volume, speed, area and more across every major unit system.
All Length Conversions
What Does This Unit Converter Cover?
This tool converts between the most commonly needed units across eight categories: Length (metres, feet, miles, kilometres, inches, yards, light years), Weight/Mass (kilograms, pounds, ounces, grams, tonnes, stone), Temperature (Celsius, Fahrenheit, Kelvin), Volume (litres, gallons, millilitres, cups, fluid ounces, pints), Speed (km/h, mph, m/s, knots), Area (sq metres, sq feet, acres, hectares, sq kilometres), Data Storage (bytes, kilobytes, megabytes, gigabytes, terabytes), and Time (seconds, minutes, hours, days, weeks).
All conversions use internationally standardised conversion factors and update in real time as you type. The "All conversions" panel shows the input value converted into every unit in that category simultaneously — useful when you need a quick reference across the board.
Who Uses a Unit Converter?
Cooking & Baking
Converting American cups and tablespoons to grams and millilitres, or Fahrenheit oven temperatures to Celsius, is one of the most common everyday conversion needs.
Travel & Navigation
Switching between miles and kilometres for distances, kilograms and pounds for luggage allowances, or reading local temperatures in unfamiliar units.
Construction & DIY
Building projects often require converting between metric and imperial measurements — metres to feet, square metres to square feet, litres of paint to gallons.
Tech & Data
Understanding file sizes, storage capacity, and data transfer speeds requires constant switching between bytes, kilobytes, megabytes, gigabytes, and beyond.
Conversions update instantly as you type — no button clicking needed.
Up to 10 significant figures, using internationally standardised conversion factors.
Once loaded, the converter works with no internet connection needed.
No account, no ads, no limits. Convert as many units as you need.
Need More Advanced Calculations?
For scientific, engineering, or financial calculations beyond basic unit conversion, these tools go further with formulas, equation solving, and professional-grade precision.
Frequently Asked Questions
How accurate are the conversions?
All conversions use the exact standard conversion factors defined by SI (International System of Units) and other official measurement bodies. Results are shown to up to 10 significant figures. For everyday use, these results are as accurate as you'll ever need.
Why does temperature conversion work differently from the others?
Most unit conversions are just multiplication (e.g., 1 foot = 0.3048 metres). Temperature conversions require both multiplication and addition because the scales have different zero points. For example, 0°C = 32°F, so you can't simply multiply — the formula is °F = (°C × 9/5) + 32. This tool handles all of that automatically.
What's the difference between mass and weight?
Scientifically, mass (kilograms, grams) measures the amount of matter in an object, while weight measures gravitational force (Newtons). However, in everyday use, most people treat them interchangeably, and most "weight" conversions (pounds, kilograms) are actually comparing mass. This converter handles everyday weight/mass conversions as they're commonly used.
Can I use this on my phone?
Absolutely. The converter is fully responsive and works on any screen size — phone, tablet, or desktop. It also works without an internet connection once the page has loaded.
Frequently Asked Questions
What unit categories are supported?
The converter supports length (metres, feet, inches, miles, km), weight/mass (kg, lbs, ounces, stones), temperature (Celsius, Fahrenheit, Kelvin), volume (litres, gallons, pints, cups), speed (km/h, mph, m/s, knots), area (sq metres, sq feet, acres, hectares), and data storage (bytes, KB, MB, GB, TB).
How accurate are the conversions?
All conversions use precise standard conversion factors. Results are shown to 6 significant figures by default. For scientific or engineering use where extreme precision is required, verify results against a reference standard.
Can I convert between imperial and metric?
Yes — all categories support both metric and imperial units. Simply select your input and output units and the conversion happens instantly as you type.
Why is temperature conversion different from the others?
Length, weight, and volume conversions are multiplicative (multiply by a fixed factor). Temperature requires both multiplication and addition because the scales have different zero points. The converter handles this correctly for all temperature pairs.
Does it work offline?
Yes — once the page is loaded, the converter works entirely in your browser with no internet connection required. All conversion logic is built into the page.