1. First Band (Left):
- Black: 0
- Brown: 1
- Red: 2
- Orange: 3
- Yellow: 4
- Green: 5
- Blue: 6
- Violet: 7
- Grey: 8
- White: 9
2. Second Band:
The second color band represents the second digit of the resistance value. The same colors as the first band are used, but white is not used in the second band.
3. Third Band (Multiplier):
The third color band indicates the multiplier to be applied to the resistance value. The colors and their corresponding multipliers are:
- Black: x1
- Brown: x10
- Red: x100
- Orange: x1,000
- Yellow: x10,000
- Green: x100,000
- Blue: x1,000,000
- Violet: x10,000,000
- Grey: x100,000,000
- White: x1,000,000,000
4. Fourth Band (Optional: Tolerance):
The optional fourth color band indicates the tolerance of the resistor value. The tolerance is the maximum deviation of the actual resistance value from the nominal value. The colors and their corresponding tolerances are:
- Brown: ±1%
- Red: ±2%
- Green: ±0.5%
- Blue: ±0.25%
- Violet: ±0.1%
If there is no fourth band, the default tolerance is usually ±5% or ±10% (depending on the resistor type and precision).
To determine the resistance value of a resistor, read the color bands from left to right. The first two bands indicate the first two digits of the resistance value, and the third band indicates the multiplier. For example, if a resistor has the color bands brown-black-orange, its resistance value is 10 x 100 = 1,000 ohms. If there's a fourth band, such as red, it indicates a tolerance of ±2%.