Decode through-hole colour codes and SMT 3-digit codes for inductors
Through-hole inductors use a colour-code system identical to resistors but the base unit is µH. SMT inductors use a 3-digit code with the base unit in nH, or R-notation where R replaces the decimal point (e.g. 4R7 = 4.7 µH).
Code 101 = 10 × 10¹ nH = 100 nH. Code 220 = 22 × 10⁰ nH = 22 nH. Same structure as the capacitor code but in nH.
Every inductor has parasitic capacitance. At the SRF the component resonates and behaves as a capacitor, not an inductor. Always choose an inductor whose SRF is well above your operating frequency.