Resistor Color Code Calculator
Determine resistance and tolerance from color bands.
Resistor Value from Color Bands
Understanding Resistor Color Codes
Resistor color codes are used to indicate the resistance value, tolerance, and sometimes the temperature coefficient of a resistor. These codes are standardized by EIA (Electronic Industries Alliance) and are essential for identifying components in electronic circuits.
How to Read Resistor Color Codes
Resistors typically have 4, 5, or 6 color bands. The most common are 4-band and 5-band resistors.
- 4-Band Resistors: First two bands are significant digits, third band is the multiplier, and the fourth band is the tolerance.
- 5-Band Resistors: First three bands are significant digits, fourth band is the multiplier, and the fifth band is the tolerance. (A 6th band, if present, indicates temperature coefficient).
Resistor Color Code Chart
| Color | Digit | Multiplier | Tolerance | Temp. Coeff. (ppm/K) |
|---|---|---|---|---|
| Black | 0 | x1 | ||
| Brown | 1 | x10 | ±1% | 100 |
| Red | 2 | x100 | ±2% | 50 |
| Orange | 3 | x1k | 15 | |
| Yellow | 4 | x10k | 25 | |
| Green | 5 | x100k | ±0.5% | |
| Blue | 6 | x1M | ±0.25% | 10 |
| Violet | 7 | x10M | ±0.1% | 5 |
| Gray | 8 | |||
| White | 9 | |||
| Gold | x0.1 | ±5% | ||
| Silver | x0.01 | ±10% | ||
| None | ±20% |
Frequently Asked Questions
What is the purpose of a resistor?
A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.
What is tolerance in a resistor?
Tolerance indicates the permissible deviation of the actual resistance value from its nominal (marked) value, expressed as a percentage. For example, a 100 Ohm resistor with ±5% tolerance will have an actual resistance between 95 Ohms and 105 Ohms.