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Resistance calculator

Resistance = voltage magnitude ÷ current magnitude.

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Answer

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Resistance = voltage magnitude ÷ current magnitude.

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Precision and calculation record
Rounding changes displayed numbers, not the calculation. Text, fractions, matrices and CSV schedules keep their own formatting. Automatic keeps up to 12 significant digits, with money shown to cents where applicable.
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    Formula and assumptions
    Uses DC or purely resistive behavior. Reactive AC impedance is a different quantity.
    Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.
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    Updated 
    Using Resistance calculator
    Resistance = voltage magnitude ÷ current magnitude.
    Uses DC or purely resistive behavior. Reactive AC impedance is a different quantity.
    Next: Voltage calculator
    A worked example
    With voltage magnitude (v) = 12, current magnitude (a) = 3, the resistance (ω) is 4.
    Next: Wattage calculator
    Before you use the result
    Uses DC or purely resistive behavior. Reactive AC impedance is a different quantity.
    Example results for voltage magnitude (v)
    These examples use Current magnitude (A): 3. They are reference calculations, not recommended settings.
    Voltage magnitude (V)Resistance (Ω)
    62
    124
    248
    Cite this page
    ToolOctopus. “Resistance calculator.” Updated 2026-09-26. https://tooloctopus.com/resistance-calculator.
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