LED Resistor Calculator
Calculate resistor values and wattage ratings for series or parallel current-limiting LED circuits.
Circuit Configuration
Common LED Colors
Schematic Diagram
Resistor Resistance
Exact value:
150.0 Ω
Nearest E24 (5%):
150.0 Ω
Nearest E12 (10%):
150.0 Ω
Resistor Power Rating
Power Dissipated:60.0 mW
Min Resistor Wattage:1/8 W (0.125W)
Safety Margins: Resistors get hot during operation. Choosing a power rating that is at least 2x the actual dissipated power extends circuit lifespan and prevents fire hazards.
Current limiting resistors for electronics design
Light Emitting Diodes (LEDs) possess a non-linear voltage-current relationship. Without a series current-limiting resistor, the diode will draw excessive current from the power supply, resulting in immediate thermal failure.
The ohm index formula is: R = (Vcc - N × Vf) / If for series chains. Standard manufacturing classifications define the E12 and E24 logarithm series.
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