Free online unit converter tools
Ten instant unit converters that run entirely in your browser. Convert length, weight, temperature, speed, volume, energy, and more — no signup, no upload.
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Centimeters to Inches
Convert centimeters to inches or inches to centimeters instantly. Includes a full reference table.
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Kilograms to Pounds
Convert kilograms to pounds or pounds to kilograms. Also shows stones and ounces.
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Celsius to Fahrenheit
Convert Celsius to Fahrenheit, Fahrenheit to Celsius, or either to Kelvin.
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MPH to KPH
Convert miles per hour to kilometers per hour, or kph to mph. Also shows m/s and knots.
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Liters to Gallons
Convert liters to US or UK gallons. Also shows fl oz, cups, pints, and quarts.
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Calories to Kilojoules
Convert kcal to kJ or kJ to kcal. Also shows calories (cal) and joules (J).
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Millimeters to Points
Convert between mm, pt, px, inches, and cm for print and web typography.
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Bytes to Readable
Convert a raw byte count to a human-readable size in both SI (decimal) and IEC (binary) units.
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Seconds to Duration
Convert seconds to days, hours, minutes, and seconds. Shows HH:MM:SS and plain English.
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Scientific Notation
Convert numbers to and from scientific notation. Also shows engineering notation.
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Why use browser-based unit converters?
Every converter here runs entirely inside your browser — no server round trips, no account needed, no data sent to a third party. Whether you are converting centimeters to inches for a recipe, kilograms to pounds for a shipping label, or bytes to megabytes for storage planning, all calculations happen locally and results are instant.
Choosing the right converter
Use the Centimeters to Inches converter for everyday length conversions. The Celsius to Fahrenheit converter is handy for weather and cooking. For nutrition labels, use Calories to Kilojoules. Designers working across print and screen will find the Millimeters to Points converter essential. For data sizes, Bytes to Readable shows both SI and IEC representations at a glance.