UnitNinja is a fast, free, and beautiful unit converter that handles all your conversion needs. No sign-up required, no clutter — just instant results as you type.
Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles. Perfect for construction, science, and everyday measurements.
Easily convert milligrams, grams, kilograms, pounds, ounces, stone, tons, and metric tons. Ideal for cooking, fitness, and shipping calculations.
Switch between Celsius, Fahrenheit, and Kelvin instantly. Essential for weather, cooking, and scientific applications.
Convert milliliters, liters, US gallons, UK gallons, cups, tablespoons, teaspoons, fluid ounces, pints, and quarts. Great for recipes and liquid measurements.
Calculate conversions between square millimeters, square centimeters, square meters, square kilometers, square inches, square feet, acres, and hectares. Useful for real estate and land measurement.
Convert meters per second, km/h, mph, knots, and Mach number. Perfect for physics, aviation, and automotive applications.
Switch between milliseconds, seconds, minutes, hours, days, weeks, months, and years. Handy for project planning and scheduling.
Convert bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Essential for computing and storage calculations.
Convert cooking measurements with ingredient-aware density calculations for flour, sugar, butter, and water. Makes recipe scaling effortless.
Measure things in football fields, Olympic swimming pools, Eiffel Towers, bananas, school buses, and blue whales. Because why not?
Yes! UnitNinja is completely free. The Pro version adds offline support, custom units, and favorites for a one-time $2.99 payment.
UnitNinja uses precise conversion factors based on international standards. All calculations are performed in real-time with full floating-point precision.
The free version requires an internet connection. UnitNinja Pro includes PWA support for full offline functionality.
The cooking converter accounts for ingredient density. A cup of flour weighs differently than a cup of sugar or butter, so selecting the right ingredient ensures accurate volume-to-weight conversions.
The Fun converter lets you express measurements in everyday objects like football fields, Olympic pools, bananas, and blue whales. It is great for putting sizes into perspective.
Absolutely! UnitNinja Pro allows you to add custom units and conversions. We also welcome suggestions for new built-in categories.
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