Free Electronics Calculators & Tools
Fast, accurate, and mobile-friendly calculators for engineers, students, and electronics enthusiasts. Calculate resistor values, LED resistors, voltage dividers, Ohm's Law, and more — all in your browser.
Resistor Color Code Calculator
Decode resistor color bands instantly and find resistance values with our interactive color code calculator.
LED Resistor Calculator
Calculate the perfect current-limiting resistor for your LED circuit with supply voltage, forward voltage, and current inputs.
Voltage Divider Calculator
Design voltage divider circuits with instant calculations for output voltage, current draw, and power dissipation.
Ohm's Law Calculator
Calculate voltage, current, or resistance using V=IR with instant power dissipation results for circuit design.
Why Use Our Electronics Calculators?
Lightning Fast
Instant calculations with real-time results as you type. No waiting, no loading screens.
Mobile Optimized
Works perfectly on any device — desktop, tablet, or phone. Calculate on the go.
Accurate & Reliable
Built by engineers for engineers. All formulas are verified and tested for accuracy.
AI Resistor ScannerSkip the Manual Work —
Scan Resistors Instantly
Point your phone camera at any resistor and get the value in seconds. No color charts, no guessing, no mistakes.
