Current calculator

Current = voltage ÷ resistance.

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Voltage (V)

Resistance (Ω)

Answer

…

Current = voltage ÷ resistance.

More results

Precision and calculation record

Decimal places in numeric results and text downloads

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.

Step-by-step calculation

Inputs are substituted below. Each line evaluates the next operation; intermediate values are displayed to 12 significant digits while the calculation uses full precision.

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Save the current answer, then change an input to compare. This clears when you leave.

Formula and assumptions

Applies to an ideal ohmic resistor. AC reactance, nonlinear components and wiring limits are excluded.

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 2026-09-26

Using Current calculator

Current = voltage ÷ resistance.

Applies to an ideal ohmic resistor. AC reactance, nonlinear components and wiring limits are excluded.

Next: Battery life calculator

A worked example

With voltage (v) = 12, resistance (ω) = 4, the current (a) is 3.

Next: Voltage calculator

Before you use the result

Applies to an ideal ohmic resistor. AC reactance, nonlinear components and wiring limits are excluded.

Example results for voltage (v)

These examples use Resistance (Ω): 4. They are reference calculations, not recommended settings.

Voltage (V)	Current (A)
6	1.5
12	3
24	6

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