Band Types

• 4-Band Resistors: Standard precision (±5% or ±10%), value = (first digit × 10 + second digit) × multiplier ±tolerance
• 5-Band Resistors: High precision (±1% or better), value = (first digit × 100 + second digit × 10 + third digit) × multiplier ±tolerance
• 6-Band Resistors: Ultra precision with temperature stability, same as 5-band plus temperature coefficient

Color Code Reference

• Black: 0 (×1 Ω)
• Brown: 1 (×10 Ω)
• Red: 2 (×100 Ω)
• Orange: 3 (×1 kΩ)
• Yellow: 4 (×10 kΩ)
• Green: 5 (×100 kΩ)
• Blue: 6 (×1 MΩ)
• Violet: 7 (×10 MΩ)
• Gray: 8 (×100 MΩ)
• White: 9 (×1 GΩ)
• Gold: ×0.1 Ω
• Silver: ×0.01 Ω

Tolerance Values (Precision)

• Brown: ±1% (Military/Industrial)
• Red: ±2% (Precision)
• Orange: ±3% (Precision)
• Yellow: ±4% (Precision)
• Green: ±0.5% (Ultra-precision)
• Blue: ±0.25% (Ultra-precision)
• Violet: ±0.1% (Laboratory grade)
• Gray: ±0.05% (Laboratory grade)
• Gold: ±5% (Commercial)
• Silver: ±10% (Consumer)

Temperature Coefficient (TC)

• Brown: 100 ppm/°C (±0.01%/°C)
• Red: 50 ppm/°C (±0.005%/°C)
• Orange: 15 ppm/°C (±0.0015%/°C)
• Yellow: 25 ppm/°C (±0.0025%/°C)
• Blue: 10 ppm/°C (±0.001%/°C)
• Violet: 5 ppm/°C (±0.0005%/°C)

Note: ppm = parts per million. Lower TC values indicate better temperature stability.

Practical Examples

• 4-Band: Brown-Black-Red-Gold = 1.0 × 100 = 100Ω ±5% (Common in signal termination)
• 5-Band: Red-Violet-Green-Brown-Brown = 275 × 10 = 2.75kΩ ±1% (Typical in precision voltage dividers)
• 6-Band: Blue-Gray-Yellow-Gold-Brown-Red = 684 × 0.1 = 68.4Ω ±1% 50ppm/°C (Used in measurement equipment)

Professional Tips

• Always verify critical resistors with a multimeter
• Consider temperature coefficient for circuits with significant heat or environmental changes
• Use 1% or better tolerance for precision analog circuits
• Account for power rating alongside resistance value in design
• Store precision resistors in moisture-controlled environments