🎨 Resistor Color Code Decoder
Pick the color bands on a resistor to read its resistance and tolerance.
Digits first, then a power of ten
The first bands are read as digits and written side by side; the multiplier band scales that number:
4-band: (d1 d2) × multiplier ± tolerance
5-band: (d1 d2 d3) × multiplier ± toleranceThe page opens on brown, black, brown, brown. Brown-black reads as 10, the brown multiplier is ×10, and the last brown is ±1%, so the part is 100 Ω and should measure between 99 and 101 Ω. Switch to 5-band and a third digit appears, turning the same start into 105 × 10 = 1.05 kΩ.
The colour values, and which end to start at
| Black 0 | Brown 1 | Red 2 | Orange 3 | Yellow 4 |
|---|---|---|---|---|
| Green 5 | Blue 6 | Violet 7 | Gray 8 | White 9 |
- Read away from the tolerance band. It is usually gold or silver, and the gap before it is wider than the others.
- Gold and silver mean something different in the multiplier position: ×0.1 and ×0.01. Brown-black-gold is 1 Ω, not 100.
- No band at all is ±20%, the old three-band convention.
Frequently asked questions
What are the colors for a 10k resistor?
Brown, black, orange, then gold for a 5% part. Brown-black is 10 and orange multiplies by 1,000, giving 10,000 ohms.
Which end of a resistor do you read first?
The end furthest from the tolerance band. Gold or silver at one end tells you that is the last band, so turn the part around and start from the other side.
What does a gold band mean on a resistor?
It depends where it sits. As the last band it means 5% tolerance; as the multiplier it divides by ten, which is how sub-10-ohm values are marked.