🔧 Resistor Color Code Calculator

How Resistor Color Codes Work

Resistors use colored bands to indicate their value, tolerance, and sometimes temperature coefficient. Each color corresponds to a digit, multiplier, or tolerance value. For a 4-band resistor, the first two bands are digits, the third is the multiplier, and the fourth is tolerance. 5-band resistors add a third digit for higher precision. 6-band resistors include a temperature coefficient indicating how much the value changes with temperature.

Color Code Table

• Digit bands: Black (0), Brown (1), Red (2), Orange (3), Yellow (4), Green (5), Blue (6), Violet (7), Gray (8), White (9)
• Multiplier: Same as digits, plus Gold (×0.1) and Silver (×0.01)
• Tolerance: Brown (±1%), Red (±2%), Green (±0.5%), Blue (±0.25%), Violet (±0.1%), Gray (±0.05%), Gold (±5%), Silver (±10%), None (±20%)
• Temperature Coefficient (6-band): Brown (100 ppm/°C), Red (50), Orange (15), Yellow (25), Blue (10), Violet (5)

FAQ

How do I read a 4-band resistor? First two bands = digits, third = multiplier, fourth = tolerance. Example: Brown-Black-Red-Gold = 10 × 100 = 1,000Ω ±5%.

What does a 5-band resistor mean? Three digit bands provide higher precision. Example: Brown-Black-Black-Red-Brown = 100 × 100 = 10,000Ω ±1%.

Which way do I read the bands? The tolerance band is usually gold, silver, or spaced slightly apart from the others. Start reading from the opposite end.

What is the temperature coefficient? It tells you how much the resistance changes per degree Celsius. A 100 ppm/°C resistor changes 0.01% per °C.