Resistor Code Calculators

Resistor Code & Electrical Calculators puts the four calculators every electronics hobbyist, student, and technician reaches for most into one simple, ad-light app that works completely offline.

RESISTOR COLOR CODE

Read 4, 5, or 6-band resistors instantly. Tap or swipe each band to match the colors on your resistor and see the resistance, tolerance, and (for 6-band) temperature coefficient — plus the guaranteed value range — update live.

INDUCTOR COLOR CODE & SMD CODE

Decode axial inductors with 3 or 4 color bands, or switch to SMD mode to look up surface-mount codes like "4R7" or "101K" and get the inductance and tolerance instantly.

CAPACITOR CODE

Dial in EIA capacitor codes (like "104" or "223K") to get the capacitance, tolerance, and value range.

OHM'S LAW CALCULATOR

Enter any two of Voltage, Current, Resistance, or Power in your preferred units (V/mV/kV, A/mA/µA, Ω/kΩ/MΩ, W/mW/kW) and instantly calculate the rest.