Electrical Calculators
Ohm's law, wattage, electricity cost, wire sizing, LED resistor, battery life.
š When to use these
Electronics projects, home wiring, calculating electricity bills, or sizing components. From basic Ohm's law to practical wire sizing and LED circuits.
Enter any 2 values (leave the third empty)
Quick examples:
V
A
Quick examples:
W
Quick examples:
A
Quick examples:
V
V
mA
Resistor
500Ī©
Power
200mW
š Step-by-step breakdown:
R = (Vsupply - Vled) / Iled
= (12V - 2V) / 20mA
= 10V / 0.02A = 500Ī©
Power = IĀ² Ć R = 0.02Ā² Ć 500 = 200 mW
Use at least a Ā¼W resistor
Quick examples:
mAh
mA
Quick examples: