Category: Electronics & Electrical Engineering

Electronic components often use color bands or printed codes to indicate their electrical values. The most common example is the resistor color code, which uses colored stripes to show resistance, tolerance, and sometimes temperature coefficient. Older capacitors also used color codes, but modern capacitors now use printed numeric markings instead.

This guide explains how to read both resistor and capacitor color codes accurately.

Resistor Color Codes

Color		Digit	Multiplier	Tolerance	Temp. Coefficient (ppm/K)
	Black	0	×1	–	250
	Brown	1	×10	±1%	100
	Red	2	×100	±2%	50
	Orange	3	×1,000	–	15
	Yellow	4	×10,000	–	25
	Green	5	×100,000	±0.5%
	Blue	6	×1,000,000	±0.25%	10
	Violet	7	×10,000,000	±0.1%	5
	Gray	8	–	±0.05%
	White	9	–	–
	Gold	–	×0.1	±5%
	Silver	–	×0.01	±10%

Usage: Color codes vs printed values

Resistors that use color‑banded:

• Through‑hole, low‑power resistors from about 1/8 W up to 2 W
• Common carbon film, metal film, and carbon composition resistors
• Used on PCBs, prototyping boards, and legacy equipment

Resistors that use printed values (no color bands):

• Surface‑mount resistors (SMD) — use numeric codes like “103” (10 kΩ), “472” (4.7 kΩ)
• Higher‑power wire‑wound resistors (5 W, 10 W, etc.) — often have the resistance and tolerance printed directly on the body
• Precision network / array resistors — usually labeled or coded in text

Resistor Band Rules

Resistors typically use 4‑band, 5‑band, or 6‑band color coding.

4‑Band Resistor

1. Band 1: First digit
2. Band 2: Second digit
3. Band 3: Multiplier
4. Band 4: Tolerance

Example: Red (2) – Violet (7) – Orange ($×1,000$) – Gold ($±5$) → $27,000 Ω ±5$

5‑Band Resistor

Used for precision resistors.

1. Band 1: First digit
2. Band 2: Second digit
3. Band 3: Third digit
4. Band 4: Multiplier
5. Band 5: Tolerance

Example: Brown – Black – Black – Red – Brown → $100 × 100 = 10 kΩ ±1$

6‑Band Resistor

Same as 5‑band, plus:

6. Band 6: Temperature coefficient (ppm/K)

Example: Blue (10 ppm/K) indicates high stability.