How do I read a resistor's value from its color bands?

Short Answer: Use the mnemonic "Bad Boys Rave Only Young Girls But Violet Goes Willingly" (Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Gray, White).

Detailed: Resistors use a color code. For a 4-band resistor (most common):

text

    Band 1   Band 2   Band 3 (multiplier)   Band 4 (tolerance)
    ┌────┐   ┌────┐   ┌────────────────┐    ┌─────────┐
    │    │   │    │   │                │    │         │
    Brown   Black   Red                 Gold
      1       0      ×100 (10²)         ±5%
    
    Value = 10 × 100 = 1000 Ω = 1 kΩ ±5%

Color code table:

Color	Digit	Multiplier	Tolerance
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%
Gray	8	×100,000,000	±0.05%
White	9	×1,000,000,000	-
Gold	-	×0.1	±5%
Silver	-	×0.01	±10%

For 5-band resistors (precision):

• First three bands = digits

• Fourth band = multiplier

• Fifth band = tolerance

Pro tip: Use a multimeter to confirm. Color blindness affects up to 8% of men — there's no shame in measuring.