LED Resistor Calculator
Minimum resistance
Suggested standard resistor
Resistor power
Suggested power rating
About this tool
Calculate a safe series resistor and power rating for LEDs.
Privacy
Your input is processed locally in your browser and is not uploaded.
Frequently asked questions
Is my input uploaded?
No. The tool works locally in your browser.
Does it work on mobile?
Yes. It is designed for phones, tablets, and desktop browsers.
Should I use the exact calculated resistor?
Choose a standard resistor value at or above the calculated resistance and verify component ratings before building a circuit.