Resistor Color Code Calculator
Decode resistor color bands to find the resistance value in ohms. Select the colors of each band on your 4-band resistor to calculate its resistance and tolerance. This resistor color code calculator uses the standard EIA color coding system used on through-hole resistors worldwide. Also see our Electric Resistance Converter.
How to Read Resistor Color Codes
- Hold the resistor with the tolerance band (gold/silver) on the right
- Read the first band — this is the first digit (1-9)
- Read the second band — this is the second digit (0-9)
- Read the third band — this is the multiplier (number of zeros to add)
- Read the fourth band — this is the tolerance (accuracy)
Color Code Reference Table
| Color | Digit | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | ×1 | — |
| Brown | 1 | ×10 | ±1% |
| Red | 2 | ×100 | ±2% |
| Orange | 3 | ×1000 | — |
| Yellow | 4 | ×10000 | — |
| Green | 5 | ×100000 | ±0.5% |
| Blue | 6 | ×1000000 | ±0.25% |
| Violet | 7 | ×10000000 | ±0.1% |
| Gray | 8 | ×100000000 | ±0.05% |
| White | 9 | ×1000000000 | — |
| Gold | — | ×0.1 | ±5% |
| Silver | — | ×0.01 | ±10% |
Common Resistor Values
| Color Bands | Resistance |
|---|---|
| Brown-Black-Red-Gold | 1 kΩ ±5% |
| Red-Red-Red-Gold | 2.2 kΩ ±5% |
| Orange-Orange-Orange-Gold | 33 kΩ ±5% |
| Yellow-Violet-Red-Gold | 4.7 kΩ ±5% |
| Brown-Black-Orange-Gold | 10 kΩ ±5% |
| Brown-Black-Yellow-Gold | 100 kΩ ±5% |
| Brown-Black-Green-Gold | 1 MΩ ±5% |
| Red-Red-Brown-Gold | 220 Ω ±5% |
| Orange-Orange-Brown-Gold | 330 Ω ±5% |
| Brown-Black-Black-Gold | 10 Ω ±5% |
Frequently Asked Questions
How do I know which end to start reading from?
The tolerance band (gold or silver) is always on the right side. If there is no tolerance band, the wider gap between bands indicates the right side. Start reading from the opposite end.
What does a gold band mean?
As a tolerance band (4th band), gold means ±5% accuracy. As a multiplier (3rd band), gold means ×0.1 (divide by 10), used for resistors below 10Ω like 4.7Ω or 2.2Ω.
What is the difference between 4-band and 5-band resistors?
4-band resistors have 2 significant digits + multiplier + tolerance. 5-band resistors have 3 significant digits + multiplier + tolerance, allowing more precise values like 47.5kΩ instead of just 47kΩ.
What is the E12 and E24 series?
E12 has 12 standard values per decade (10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82). E24 has 24 values. These are the preferred values manufacturers produce, based on geometric progressions.