Developer Tools
Resistor Color Code Calculator - 4, 5 & 6 Band
Decode resistor color bands to resistance and tolerance, or enter a resistance value to find the matching color bands. Supports 4-band, 5-band, and 6-band resistors.
How to read resistor color codes
Resistors use colored bands to indicate their resistance value and tolerance. Reading them correctly requires knowing the position of each band and what each color represents.
Color code chart
The mnemonic B B ROY of Great Britain has a Very Good Wife covers the digit colors 0–9: Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White. Gold and Silver are used only for the multiplier (×0.1, ×0.01) and tolerance bands.
4-band vs 5-band vs 6-band resistors
Most common resistors have 4 bands. Precision resistors (≤1% tolerance) typically have 5 bands for an extra digit of accuracy. High-stability or military-spec resistors add a 6th band for temperature coefficient.
Tolerance and range
A 4.7 kΩ ±5% resistor (Yellow-Violet-Red-Gold) will measure between 4,465 Ω and 4,935 Ω and still be within spec. Use tighter tolerances (±1% or ±0.5%) in precision circuits.
Full color code chart
| Color | Digit value | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | 1 | — |
| Brown | 1 | 10 | ±1% |
| Red | 2 | 100 | ±2% |
| Orange | 3 | 1 k | — |
| Yellow | 4 | 10 k | — |
| Green | 5 | 100 k | ±0.5% |
| Blue | 6 | 1 M | ±0.25% |
| Violet | 7 | 10 M | ±0.1% |
| Gray | 8 | 100 M | ±0.05% |
| White | 9 | 1 G | — |
| Gold | — | 0.1 | ±5% |
| Silver | — | 0.01 | ±10% |
Temperature coefficient (6th band)
5-band and 6-band precision resistors have a temperature coefficient band indicating how much the resistance changes with temperature (ppm/°C = parts per million per degree Celsius):
- Brown: 100 ppm/°C
- Red: 50 ppm/°C
- Orange: 15 ppm/°C (common in precision metal-film resistors)
- Yellow: 25 ppm/°C
A resistor with 100 ppm/°C and 10 kΩ nominal changes by 1 Ω per degree of temperature change.
SMD resistor codes
Surface-mount resistors (SMD/SMT) use a numeric code rather than color bands:
- 3-digit code: first two digits are significant digits; the third is the
multiplier (number of zeros). Example:
103= 10 × 10³ = 10 kΩ.470= 47 Ω (0 zeros). - 4-digit code: first three digits are significant; the fourth is the
multiplier. Example:
4702= 470 × 10² = 47 kΩ. - EIA-96 code: used for 1% precision SMDs. A two-digit number codes the significant value from a lookup table; a letter codes the multiplier.