Current Limiting LED Series Resistor Calculator
Circuit electronics and hardware design tool. Protects LED diodes from overcurrent using Ohm's Law ($R = \frac{V_s - V_f}{I_f}$).
Input Parameters
Instant Calculation Result
Adjust values on the left to calculate live results.
In-Depth Guide & Mathematical Methodology
💡 Standard LED Forward Voltages (Vf)
Red / Orange LED: Vf ≈ 1.8V - 2.1V
Yellow / Green LED: Vf ≈ 2.0V - 2.2V
Blue / White / UV LED: Vf ≈ 3.0V - 3.4V
Standard Current (If): 20 mA (0.02 A)
Frequently Asked Questions (FAQ)
What is the Current Limiting LED Series Resistor Calculator and how does it work?
Circuit electronics and hardware design tool. Protects LED diodes from overcurrent using Ohm's Law ($R = \frac{V_s - V_f}{I_f}$).
How do I use this Current Limiting LED Series Resistor Calculator?
Enter Supply Voltage ($V_s$ in Volts, e.g. 5V or 12V). Select LED Type / Color (Forward Voltage $V_f$, e.g. Red = 2.0V, Blue/White = 3.2V). Enter Desired LED Forward Current ($I_f$ in milliamps - mA, e.g. 20 mA). View Calculated Resistance (Ω), Nearest E12 Commercial Value, and Power Dissipation (W).
What mathematical formula is used in this calculation?
Resistor R = (Vs - Vf) / (If / 1000). Power P = (Vs - Vf) * (If / 1000). Use resistor rated at 2x P.
Is the Current Limiting LED Series Resistor Calculator on FindCalculator free to use?
Yes, all 330+ interactive tools on FindCalculator.online are 100% free, run directly in your browser without registration, and do not store your private calculation data.