Calculator
Electrical Engineering Calculator
Calculate Ohm's law, resistor networks, color codes, conductor resistance and resistive voltage drop.
Electrical Engineering Calculator
Calculate Ohm's law, resistor networks, color codes, conductor resistance and resistive voltage drop.
Result
Result
24 W
V, A, Ω and W
Ohm's law V = I × R and P = V × I connect voltage, current, resistance and power.
Resistor networks
Series resistances add; parallel uses reciprocal sums and a zero-ohm branch gives zero.
Voltage divider
The calculated output is ideal and unloaded. A real load across R2 changes it.
Color code
IEC 60062 4-, 5- and 6-band codes provide digits, multiplier, tolerance and optional TCR.
Conductor resistance
R = ρL/A uses one conductor's actual length. No material presets or temperature model are included.
Voltage drop
The round-trip model doubles one-way distance. Results are not cable sizing, compliance or safety approval.
Frequently asked questions
How do I calculate current?
Use voltage divided by resistance.
How do I calculate watts?
Multiply voltage and current.
How do series resistors add?
Add their resistance values.
What is two 100 Ω resistors in parallel?
50 Ω.
How does a voltage divider work?
Vout = Vin × R2 ÷ (R1 + R2) for an unloaded divider.
How are resistor bands read?
Digits, multiplier and tolerance follow IEC 60062.
How is conductor resistance calculated?
Use R = ρL/A.
How is voltage drop calculated?
Use current times total wire resistance.
Does it size cables?
No. It provides no installation or safety sizing.
Does it calculate electricity cost?
No. Use the energy-cost calculator.
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