Resistor Color Code Calculator
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Results
Yellow, Violet, Red, Gold: 4.7 kΩ ±5%
How to use the resistor color code calculator
- Choose Colors → value and the number of bands on your resistor.
- Hold the resistor with the tolerance band (often gold or silver, and usually set slightly apart) on the right, then pick each band's color from left to right.
- For the reverse, choose Value → colors and type a value such as 4.7k, 4k7 or 220.
- To combine parts, choose Series / parallel and list the values separated by commas.
Resistor color code formula
5 bands: R = (digit 1, digit 2, digit 3) × multiplier, then tolerance
6 bands: as 5 bands, plus a temperature coefficient in ppm/K
Series: R = R₁ + R₂ + … · Parallel: 1 ÷ R = 1 ÷ R₁ + 1 ÷ R₂ + …
The color code is defined in the international standard IEC 60062. The significant-figure bands are written as digits side by side, not added, and the multiplier band gives the power of ten. Tolerance is how far the actual resistance may be from the marked value; the temperature coefficient (TCR) on 6-band parts is how much it changes per degree, in parts per million per kelvin. Values are normally chosen from the IEC 60063 preferred-number series such as E12 and E24.
Worked examples
Yellow, violet, red, gold reads 4 and 7, so 47, times the red multiplier of 100: 4.7 kΩ with ±5% tolerance, so anywhere from 4.465 kΩ to 4.935 kΩ. On a 5-band part, brown, black, black, red, brown is 100 × 100 = 10 kΩ ±1%. Add a sixth brown band (red, red, black, brown, brown, brown) and you have 2.2 kΩ ±1% with a temperature coefficient of 100 ppm/K. Three resistors of 100, 220 and 330 Ω make 650 Ω in series but only 56.9 Ω in parallel: a parallel combination is always smaller than its smallest resistor.
Resistor color code chart (IEC 60062)
| Color | Digit | Multiplier | Tolerance | Temp. coefficient |
|---|---|---|---|---|
| Black | 0 | ×1Ω | – | 250 ppm/K |
| Brown | 1 | ×10Ω | ±1% (F) | 100 ppm/K |
| Red | 2 | ×100Ω | ±2% (G) | 50 ppm/K |
| Orange | 3 | ×1kΩ | ±0.05% (W) | 15 ppm/K |
| Yellow | 4 | ×10kΩ | ±0.02% (P) | 25 ppm/K |
| Green | 5 | ×100kΩ | ±0.5% (D) | 20 ppm/K |
| Blue | 6 | ×1MΩ | ±0.25% (C) | 10 ppm/K |
| Violet | 7 | ×10MΩ | ±0.1% (B) | 5 ppm/K |
| Gray | 8 | ×100MΩ | ±0.01% (L) | 1 ppm/K |
| White | 9 | ×1GΩ | – | – |
| Gold | – | ×0.1 | ±5% (J) | – |
| Silver | – | ×0.01 | ±10% (K) | – |
| Pink | – | ×0.001 | – | – |
| No band | – | – | ±20% (M) | – |
E12 resistor values and their color codes
The 12 values per decade of the E12 series, shown for 1 kΩ to 8.2 kΩ with a ±5% gold band. Other decades use the same digits with a different multiplier.
| Value | 4-band code |
|---|---|
| 1 kΩ | Brown, Black, Red, Gold |
| 1.2 kΩ | Brown, Red, Red, Gold |
| 1.5 kΩ | Brown, Green, Red, Gold |
| 1.8 kΩ | Brown, Gray, Red, Gold |
| 2.2 kΩ | Red, Red, Red, Gold |
| 2.7 kΩ | Red, Violet, Red, Gold |
| 3.3 kΩ | Orange, Orange, Red, Gold |
| 3.9 kΩ | Orange, White, Red, Gold |
| 4.7 kΩ | Yellow, Violet, Red, Gold |
| 5.6 kΩ | Green, Blue, Red, Gold |
| 6.8 kΩ | Blue, Gray, Red, Gold |
| 8.2 kΩ | Gray, Red, Red, Gold |
The E24 series adds 12 more values per decade: 1.1, 1.3, 1.6, 2, 2.4, 3, 3.6, 4.3, 5.1, 6.2, 7.5, 9.1 (× a power of ten).
Tips for reading resistors
- Start from the right end. Gold and silver never appear as the first band, so if one end is gold or silver, start from the other end.
- Check with a meter. Brown, red and orange can look alike under warm light, and heat can discolour bands. A multimeter settles it (with the part out of circuit).
- Mind the power rating. Color bands don't show it; body size usually does. Use the Ohm's law calculator to find the watts a resistor must handle.
- Surface-mount parts use numbers, not colors: "472" means 47 × 10² = 4.7 kΩ.
Working on wiring rather than circuit boards? See the voltage drop calculator. Electrical work on mains circuits must follow your local code and be done by a qualified person where required.
Frequently asked questions
How do you read a 4-band resistor?
The first two bands are digits, the third is the multiplier and the fourth is the tolerance. Yellow (4), violet (7), red (×100), gold (±5%) is 47 × 100 = 4,700 Ω, or 4.7 kΩ, and the real value can be anywhere from 4,465 to 4,935 Ω.
How is a 5-band resistor different?
A 5-band resistor has three digit bands before the multiplier, so it can show values such as 4.75 kΩ. Brown, black, black, red, brown reads 100 × 100 = 10 kΩ with ±1% tolerance. A sixth band, when present, gives the temperature coefficient in ppm/K.
Which end of a resistor do I start reading from?
Start from the end with the bands closest together. The tolerance band is usually spaced a little apart and is often gold or silver; gold and silver are never used as the first band, so if one end is gold or silver, read from the other end.
How do I calculate resistors in series and parallel?
In series, add the values: 100 + 220 + 330 = 650 Ω. In parallel, add the reciprocals and take the reciprocal of the total: 1 ÷ (1/100 + 1/220 + 1/330) ≈ 56.9 Ω. Two equal resistors in parallel give half the value of one.
What are the E12 resistor values?
The E12 series, from IEC 60063, has 12 values per decade: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68 and 82, multiplied by any power of ten (for example 4.7 kΩ or 470 Ω). Each value is about 21% above the previous one.