Resistor Color Code Calculator
Read resistor color bands instantly. Pick 4- or 5-band colors and get resistance, tolerance and the value range, with a live colored resistor preview.
1 kΩ
±5% tolerance · range 950 Ω – 1.05 kΩ
Reading the bands
Through-hole resistors print their value as colored stripes. On a 4-band resistor the first two bands are significant digits, the third is a power-of-ten multiplier, and the last (slightly separated, often gold or silver) is the tolerance. A 5-band resistor adds a third significant digit for tighter precision.
Read from the end where the bands are grouped closest together; the lone tolerance band goes on the right.
Color values
| Color | Digit | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | ×1 | — |
| Brown | 1 | ×10 | ±1% |
| Red | 2 | ×100 | ±2% |
| Orange | 3 | ×1k | — |
| Yellow | 4 | ×10k | — |
| Green | 5 | ×100k | ±0.5% |
| Blue | 6 | ×1M | ±0.25% |
| Violet | 7 | ×10M | ±0.1% |
| Grey | 8 | ×100M | ±0.05% |
| White | 9 | ×1G | — |
| Gold | — | ×0.1 | ±5% |
| Silver | — | ×0.01 | ±10% |
A memory aid
A classic mnemonic for 0–9 (Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White) is “Big Brown Rabbits Often Yield Great Big Vocal Groans When Gingerly Slapped” (the last two cover Gold and Silver multipliers). Tolerance and the value range matter for real circuits: a 100 Ω ±5% part is anywhere from 95 Ω to 105 Ω, which is why precision designs use ±1% (5-band) or better.
E-series & sanity checks
Resistors come in standard E-series values (E12, E24, E96…) so not every number you can encode actually exists as a part. If a reading looks odd, re-check the band order — a resistor read backwards gives a wildly different value, and that's the most common mistake. When in doubt, measure with a multimeter and use this tool to confirm the printed code.