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    Mass Converter & Reference

    This mass guide keeps metric and customary weight units in one place so you can verify recipes, lab notes, and shipping specs in seconds.

    Mass conversions pop up in everything from baking to freight forwarding. Use the reference below to see how each unit ties back to the SI kilogram and to learn the shortcuts professionals rely on.

    Base unit

    Kilogram (kg)

    Units covered

    6

    Popular conversions

    2

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    Unit breakdown

    Every unit below references the SI base value so you can compare readings quickly.

    UnitSymbol1 unit in kgNotes
    Milligrammg1 mg = 1.0000×10^-6 kg
    Gramg1 g = 0.001 kg
    Ounceoz1 oz = 0.0283495 kg
    Poundlb1 lb = 0.453592 kg
    KilogramkgReference unit
    Metric Tont1 t = 1K kg

    Popular conversions

    These presets mirror the quick actions available inside the SwapUnits converter.

    Launch converter
    ConversionExampleReference pageWhy it matters
    Kilograms to Pounds1 kg = 2.20462 lbOpenIdeal for quick checks inside the live converter.
    Grams to Ounces1 g = 0.035274 ozOpenIdeal for quick checks inside the live converter.

    Frequently asked questions

    What is the difference between mass and weight?

    Mass measures how much matter an object contains, while weight is the force exerted by gravity on that mass. Everyday conversions treat them similarly, but scientific calculations distinguish the two.

    Why is the kilogram the base SI unit instead of the gram?

    The International System of Units chose the kilogram as the base unit so that the derived unit for force (newton) maintains practical magnitudes in physics and engineering.

    How accurate is the gram-to-ounce relationship?

    The conversion 1 ounce = 28.3495 grams is exact enough for gourmet baking and nutrition labels. For pharmaceutical precision, convert to milligrams and work with mass balances.

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    Head back to the SwapUnits converter to crunch numbers instantly and save your favorite presets.

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