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Multiply lb by 0.45359237 to get kg.
Frequently used converters
Start with the most popular measurement tasks.
Explore by measurement
Purpose-built converters for 16 distinct physical quantities.
Weight & mass
Mass measures the amount of matter. US customary pounds and international kilograms are common.
Length
Length uses exact definitions for the international foot and inch.
Volume & cooking
US customary volume measures are different from UK imperial measures. Fluid ounces measure volume, not mass.
Temperature
Temperature scales require an offset as well as a scale factor.
Pressure
Pressure is force per unit area. Bar, psi, kPa and atmospheres are not units of force.
Torque
Torque is the turning effect of a force. Pound-force foot (ft·lbf) is distinct from mass pounds.
Time
Convert precise durations between milliseconds, seconds, minutes, hours and days.
Speed
Speed represents distance traveled per unit time.
Area
Square units measure two-dimensional area, not linear length.
Force
Pound-force (lbf) is force and should not be confused with pound mass (lb).
Digital storage
Decimal GB = 1,000 MB, whereas binary GiB = 1,024 MiB.
Density
Density relates mass to volume. Converting mass to volume additionally requires a known density.
Power
Power expresses the rate at which work is done.
Acceleration
Acceleration is the rate of change of speed over time.
Fuel economy
US MPG and liters per 100 km are reciprocal measures; zero requires special handling.
Flow rate
Volumetric flow is a volume passing per unit time.
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Every tool shows its formula and consistent unit definitions. We distinguish US fluid ounces from weight ounces and imperial units from US customary units.
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