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Resistor Color Code Calculator

Every resistor has colored bands that encode its value. Master these and you can read any resistor at a glance — a core skill every electronics engineer needs.

Bands Value

Select the color bands you see on a real resistor

220Ω
Tolerance ±5% → range: 209Ω231Ω
= (22) × 10 Ω

🔢 Value Bands

Enter a resistance, see the color code

Red
digit 1
Red
digit 2
Brown
mult
Gold
tol

📊 Complete Color Band Reference

ColorSwatchDigitMultiplierTolerance
Black
0×1
Brown
1×10±1%
Red
2×100±2%
Orange
3×1,000
Yellow
4×10,000
Green
5×100,000±0.5%
Blue
6×1,000,000±0.25%
Violet
7×10,000,000±0.1%
Grey
8±0.05%
White
9
Gold
×0.1±5%
Silver
×0.01±10%

🧠 Memory tip — "BB ROY of Great Britain has Very Good Wife"

Black (0)  Brown (1)  Red (2)  Orange (3)  Yellow (4)  Green (5)  Blue (6)  Violet (7)  Grey (8)  White (9)

Then Gold = ×0.1 (5% tol), Silver = ×0.01 (10% tol). The 4th band is always Gold or Silver on common resistors.