Electronics
Resistor calculators, Ohm's law solvers, LED resistor pickers, and other electronics utilities.
Free online electronics calculators — resistor color codes, Ohm's law, LED resistors, PCB trace width, capacitor charge time, and voltage dividers. Quick reference and design helpers for makers, hobbyists, and EE students.
4 tools · always free · no account needed
Resistor Calculator
Visual resistor color code calculator with reverse lookup
Ohm's Law Calculator
Calculate voltage, current, resistance, and power
LED Resistor Calculator
Calculate series resistor for LEDs with circuit diagram
PCB Trace Calculator
Calculate PCB trace width using IPC-2221 standard
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