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How it works
Select a category
Choose Length, Weight, Temperature, Speed, Area, or Volume from the category tabs at the top.
Choose your units
Pick the source unit (e.g., kilometres) and target unit (e.g., miles) from the dropdowns on each side.
Enter a value
Type a number in either input field. The converted value appears instantly in the other field. No 'convert' button needed.
Why use Ozaar Unit Converter?
6 measurement categories
Length, Weight/Mass, Temperature, Speed, Area, and Volume, all the everyday conversions you need in one place.
Precise temperature formulas
Celsius, Fahrenheit, Kelvin, and Rankine use exact formulae (not linear factors) for 100% accurate temperature conversion.
Bi-directional input
Type in either field and the other updates instantly. Change the unit dropdowns and both values recalculate immediately.
Metric and imperial
Covers both metric (SI) and imperial units. Convert km to miles, kg to lbs, litres to gallons, and more with one click.
Real-world use cases
International recipes
Convert American recipes from cups and ounces to grams and millilitres. Convert Fahrenheit oven temperatures to Celsius instantly.
Try it for this →Home Cook
Traveller
Travel and navigation
Convert between mph and km/h for speed limits, miles and kilometres for distances, and Fahrenheit and Celsius for weather.
Try it for this →Engineering and science
Convert between imperial and metric units for engineering calculations, material quantities, and cross-standard specifications.
Try it for this →Engineer
What is a Unit Converter?
A unit converter is a calculation tool that translates a quantity from one unit of measurement to another. Common conversions include length (metres to feet), weight (kilograms to pounds), temperature (Celsius to Fahrenheit), speed (km/h to mph), area (square metres to square feet), and volume (litres to gallons). These conversions are needed daily in cooking, travel, science, engineering, and everyday life.
The world uses two major measurement systems, the metric system (SI units) and the imperial system (used primarily in the United States and informally in the UK). Converting between them requires precise conversion factors. Temperature is special: it requires a formula rather than a simple multiplication factor, because the scales have different zero points.
Ozaar Unit Converter covers 6 measurement categories with 50+ unit types, bi-directional input, and exact temperature formulae, all in a clean, instant browser-based interface.
How does Unit Converter work?
Most unit conversions use a multiplication factor: for example, 1 kilometre = 0.621371 miles, so multiplying kilometres by 0.621371 gives miles. Our converter stores these factors in a lookup table and applies them when you enter a value.
Temperature is handled differently. Converting Celsius to Fahrenheit uses the formula °F = (°C × 9/5) + 32. Converting to Kelvin uses K = °C + 273.15. All four temperature scales (Celsius, Fahrenheit, Kelvin, Rankine) can be converted to any other by first converting to Celsius as an intermediate step.
Why use a browser-based Unit Converter?
A browser-based unit converter is always available without app installation, works on any device, and doesn't require an internet connection after first load. It is faster than searching 'convert X to Y' on Google and seeing the search engine's built-in converter, with clearer display and bi-directional input.
Our converter shows full floating-point precision by default, which is useful for scientific or engineering applications where rounding matters. For everyday use, the values are rounded to a human-readable number of decimal places.
You might also want to convert between world currencies or calculate time-based values using our free browser tools.
Frequently asked questions
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