IEC 60062: Marking Codes for Resistors and Capacitors

Reading Resistor Color Codes: The Engineer Second Language

IEC 60062:2016 specifies marking codes for resistors and capacitors — the color-band system and the RKM letter-and-digit code. This is an electronics engineer second language.

Color-band formula: 4-band = (first two bands) × 10^{third band} ± tolerance band. 5-band adds one more significant digit. Colors: Black 0, Brown 1, Red 2, Orange 3, Yellow 4, Green 5, Blue 6, Violet 7, Grey 8, White 9. Tolerances: Brown ±1%, Red ±2%, Gold ±5%, Silver ±10%.

RKM code: Letters replace decimal points — 4R7 = 4.7 Ω, 2K2 = 2.2 kΩ, 1M0 = 1.0 MΩ. R = Ω (no multiplier), K = kΩ (×10³), M = MΩ (×10⁶). This method is more reliable than decimal-point marking — a decimal point can wear off small components and become unreadable.

TN Lab — Every electronics engineer should read color codes as fluently as their native language.