UnitConv

Circuit & Ohm’s Law Lab

Build a circuit, slide the voltage and resistance, and watch Ohm’s law V = I·R light it up — with series vs parallel side by side.

This is an exact DC circuit solver — no faked numbers. Pick a preset or add resistors, switch between series and parallel, and tune the battery voltage and each resistance. Watch the current I = V/R flow as charge carriers, the bulb brighten with its power, and the table show how series circuits share one current while parallel branches share one voltage.

Ohm’s law · I = V / R
I = 9 V / 0 Ω = 0.00 A
Total resistance: 0 ΩTotal power: P = V·I = 0.00 W
Series · 0R
Wiring

Presets

Per-resistor breakdown

RVoltage dropCurrentPower
Total resistance: 0 ΩTotal current: 0.00 A

Selected resistor

Tap a resistor on the canvas, a chip, or a row in the table to read its voltage drop, current and power — and adjust its resistance live.

Formulas & sources

V = I·R

P = V·I = I²R = V²/R

Series: R = Σ R

Parallel: 1/R = Σ 1/R

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