Electronics Tools
Free online calculators and tools for electronics engineers and hobbyists. Resistor calculators, LED calculators, and more.
Electronics Calculators for Your Projects
Our free electronics calculators help you plan and implement your electronics projects. From Arduino and Raspberry Pi to complex circuits – these tools support you with calculations for resistors, LEDs, and electrical fundamentals.
All calculators work entirely in your browser – no data is sent to servers. 100% privacy-first, no signup required.
Available Tools
LED Resistor Calculator
Calculate the correct resistor value for LEDs based on supply voltage and LED specifications. Supports single LEDs, series, and parallel configurations. Essential for Arduino, Raspberry Pi, ESP32, and electronics projects. Includes power dissipation warnings and standard E24 resistor suggestions.
Resistor Color Code Calculator
Calculate resistor values from color bands or find the color code for a given resistance value. Supports 4-band, 5-band, and 6-band resistors following IEC 60062 standard. Perfect for electronics engineers, hobbyists, and students working with through-hole resistors.
Ohm's Law Calculator
Calculate voltage, current, resistance, or power using Ohm's Law. Enter any two values to find the others. Essential tool for electronics engineers, students, and hobbyists working with electrical circuits. Understand the fundamental relationship between voltage (V), current (I), resistance (R), and power (P) in DC circuits.
Popular Use Cases
Arduino & Raspberry Pi Projects
Calculate the correct resistors for LED circuits in your microcontroller projects.
Electronics Prototyping
Use our calculators for quick calculations during circuit development.
Education & Learning
Understand electrical fundamentals with interactive calculators and examples.
Repair & Maintenance
Identify resistor values through color code recognition for repairs.
Additional Resources
Visit our blog page for detailed tutorials and guides on electronics projects.
View All Tools