Unit converter

Use this unit converter to convert mm to inches, kg to lbs, and many more in areas like mechanics, electricity, magnetism, acoustics, etc

Unit converter

This tool allows you to convert different units of measurement in subjects such as mechanics, electricity, magnetism, acoustics, photometry, radioactivity, motion, etc. These are all the magnitudes for which units can be converted:

    • Length
    • Area
    • Volume
    • Speed
    • Acceleration
    • Speed ​​(Angular)
    • Acceleration (Angular)
    • Mass
    • Temperature
    • Specific volume
    • Density
    • Volume (Dry)
    • Force
    • Pressure
    • Energy;
    • Power
    • Moment of force
    • Moment of inertia
    • Torque
    • Energy density
    • Specific energy
    • Magnetomotive force
    • Magnetic field strength
    • Magnetic flow
    • Magnetic induction
    • Charge
    • Linear charge density
    • Surface charge density
    • Volume charge density
    • Current
    • Linear current density
    • Surface current density
    • Electric field strength
    • Electric potential
    • Electric resistance
    • Electrical conductance
    • Electrical conductivity
    • Electrostatic capacitance
    • Inductance
    • Thermal expansion
    • Thermal resistance
    • Thermal conductivity
    • Specific heat
    • Heat density
    • Heat flow density
    • Heat transfer coefficient
    • Luminance
    • Luminous intensity
    • Illuminance
    • Wavelength
    • Sound
  10. FLUIDS
    • Flow (liquid)
    • Flow (mass)
    • Flow (molar)
    • Mass flow density
    • Concentration (molar)
    • Concentration (mass)
    • Viscosity (dynamic)
    • Viscosity (kinematics)
    • Surface tension
    • Permeability
    • Radiation
    • Radiation (activity)
    • Radiation (exposure)
    • Radiation (absorbed dose)
    • Typography
    • Numbers
    • Prefixes
    • Digital resolution
    • Energy efficiency
    • Data storage

Units of measure

The measurements of physical quantities are expressed in units of measurement. A unit of measurement is a standardized quantity (kg) of a given physical quantity (weight) that is defined by convention or by law. Any value of a physical quantity can be expressed as a multiple of the unit of measure.A unit of measure takes its value from a pattern or a combination of other units previously defined. The first units are known as base (fundamental) units, while the second are called derived units.

Without standardized units, it would be very difficult to express and compare measurement values: how could we know which of two people weighs more if the weight of one is expressed in kilograms and the weight of the other is expressed in pounds?

System of units

A system of units is a consistent, normalized and uniform set of units of measure in which no magnitude has more than one associated unit. In the world there are currently two main systems of units:

  • International System (SI): it is the most modern and most used system at present. It is the legal system in most countries and the one used in the scientific and mathematical field. The International System of Units defines seven basic or fundamental units that are independent from the dimensional point of view. These basic SI units and their physical quantities are the meter for the length, the kilogram for the mass, the second for the time, the ampere for the electric current intensity, the kelvin for the temperature, the candela for the luminous intensity and the mole for the amount of substance.
  • Imperial or Statutory System: it is the traditional Anglo-Saxon system. In 1824 it was normalized in the United Kingdom under the name of Imperial System, whose use remains in the current life of this country. It was also normalized in the United States, with some differences over the Imperial System, and the latter is only used as a legal system in the United States.

In addition to the previous systems, there are other less relevant systems at present, such as:

  • Metric system decimal: first unified system of measurements; its basic units were: the meter and the
  • Cegesimal System of Units (CGS): so named because its basic units are the centimeter, the gram and the second. It was created as an extension of the metric system for scientific uses.
  • Natural System: in which the units are chosen so that certain physical constants are worth exactly the unit.
  • Units Technical System: derived from the metric system with units created for technical uses and based on the previous one. This system is in disuse.

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