Resistor Color Code
Through-hole resistors use colored bands painted on the body to indicate their resistance value. This calculator supports both 4-band (2 digits + multiplier + tolerance) and 5-band (3 digits + multiplier + tolerance) resistors. Select the color of each band to instantly decode the resistance.
Brown
Black
Red
Gold
Decoded value
Resistance1.000 kΩ
Tolerance±5%
Acceptance range950 Ω … 1.050 kΩ
Formulas used
4-Band: (Band1×10 + Band2) × Multiplier ± Tolerance5-Band: (Band1×100 + Band2×10 + Band3) × Multiplier ± Tolerance
How to use this calculator
Step-by-Step Instructions
- Determine the band count Most standard resistors have 4 bands. Precision resistors typically have 5 bands. Select the correct type from the dropdown.
- Orient the resistor correctly Hold the resistor so the tolerance band (usually gold or silver) is on the right side. Read the bands from left to right.
- Select each band color Use the dropdown menus to match the colors you see on the physical resistor.
- Click “Decode Resistance” The calculator instantly shows the resistance value in Ohms, kΩ, or MΩ along with the tolerance range.
Worked Example
4-band resistor with Brown-Black-Red-Gold bands:
Brown=1, Black=0 digits “10” | Red=×100 multiplier | Gold=±5% tolerance
Result: 10 × 100 = 1,000Ω (1kΩ) ±5% Range: 950Ω to 1,050Ω
Pro Tips
- The tolerance band is usually slightly separated from the other bands this helps you orient the resistor correctly.
- If you cannot distinguish between brown and red under poor lighting, use a multimeter to verify the reading.
- Common memorization mnemonic: B ad B eer R ots O ur Y oung G uts B ut V odka G oes W ell (Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White).