With this resistor color code calculator, you'll quickly and easily find out the resistance of your resistor component. Just choose how many bands your resistor has – 4, 5, or 6, select the colors, and in the blink of an eye, you'll get the resistance with tolerance, range, and temperature coefficient value (if you've chosen a 6-band resistor color code).
If you want to understand how to read resistor color code, scroll down, and you'll find the formulas and explanation. We also show the 10k resistor color code as well as many other informative examples.
How to read resistor color code?
Color bands are an easy and cheap way of indicating the value of an electronic component. The printed alphanumeric codes would be too small to read on the tiniest resistors, so the color code was developed in the early 1920s.
The first question which usually arises is: how do I know from which end I should start reading my resistor color code? Fortunately, a couple of visual hints exist:
- In a usual case, the bands are not spaced regularly – there's a gap, and bands are somehow grouped. The larger gap occurs before the tolerance band. The bigger group points to the start from which you should begin reading the resistor value.
- Very often, the tolerance of the resistor is equal to 5% or 10%. These values are marked with metallic colors – gold and silver, respectively. The resistor color code never starts from such a color – so if you find a metallic color on your resistor, it's definitely the tolerance value, and it must be placed at the end.
- Usually, the first band will be closest to the end (but not always, so use the other clues too).
- If none of the above help, you can always use a multimeter to tell between two possible resistances – and reading directions.
The value of the resistance is marked with colors. Every color is a different number. This is the color code working for the first 2 or 3 bands from the start:
| Color | Digit |
|---|---|
| Black | 0 |
| Brown | 1 |
| Red | 2 |
| Orange | 3 |
| Yellow | 4 |
| Green | 5 |
| Blue | 6 |
| Violet | 7 |
| Gray | 8 |
| White | 9 |
Then, we have the band called the multiplier. Here, color represents the power of 10 by which the number created from the previous bands must be multiplied:
| Color | Multiplier |
|---|---|
| Black | ×1 Ω |
| Brown | ×10 Ω |
| Red | ×100 Ω |
| Orange | ×1 kΩ |
| Yellow | ×10 kΩ |
| Green | ×100 kΩ |
| Blue | ×1 MΩ |
| Violet | ×10 MΩ |
| Gray | ×100 MΩ |
| White | ×1 GΩ |
| Gold | ×0.1 Ω |
| Silver | ×0.01 Ω |
You can express the multipliers with prefixes like kilo, mega, or giga (kΩ, MΩ, GΩ), but scientific notation is also used – e.g., 109 Ω (gigaohm).
Finally, the last band – which occurs in all types of resistors (4, 5, and 6-band) – is the tolerance band. It's expressed as a percentage, and the variation in component resistance is mostly statistical in nature (a normal distribution):
| Color | Tolerance |
|---|---|
| Brown | ±1% |
| Red | ±2% |
| Green | ±0.5% |
| Blue | ±0.25% |
| Violet | ±0.1% |
| Gray | ±0.05% |
| Gold | ±5% |
| Silver | ±10% |
| None | ±20% |
For 6-band resistors, there's an additional ring indicating the temperature coefficient (in ppm/K), which describes how much the resistance changes per degree of temperature.
Example of how to use this resistor color code calculator
Suppose you have a 4-band resistor with bands: Yellow, Violet, Red, Gold.
2nd digit (Violet) = 7
Multiplier (Red) = ×100
Tolerance (Gold) = ±5%
R = 47 × 100 = 4,700 Ω = 4.7 kΩ ±5%
4-band resistor color code
The 4-band resistor is the most common type. The first two bands are the significant digits, the third band is the multiplier, and the fourth band is the tolerance:
5-band resistor color code
The 5-band resistor adds a third significant-digit band for greater precision. The first three bands are digits, the fourth is the multiplier, and the fifth is the tolerance:
6-band resistor color code
The 6-band resistor is identical to the 5-band one, but adds a sixth band for the temperature coefficient (ppm/K). This tells you how much the resistance will drift with temperature – important for precision and high-stability applications.
What's the 10k resistor color code?
A 10 kΩ (10,000 Ω) resistor is one of the most common values. Its 4-band color code is:
1 (Brown), 0 (Black), ×1 kΩ (Orange), ±5% (Gold)
R = 10 × 1,000 = 10,000 Ω = 10 kΩ ±5%
For a 5-band 10 kΩ resistor with ±1% tolerance, the code is Brown, Black, Black, Red, Brown.
Unit systems
Resistance is measured in ohms (Ω), the SI unit, which is used identically in both the metric and American engineering systems. This calculator automatically scales the result to the most readable prefix – Ω, kΩ (kilohm), MΩ (megaohm), or GΩ (gigaohm). The temperature coefficient of a 6-band resistor is given in ppm/K, which is numerically identical to ppm/°C.
FAQs
How do I know which end of the resistor to read first?
Start from the end where the bands are grouped more closely together. The tolerance band (often gold or silver) is set slightly apart and is read last.
What does a gold or silver band mean?
As a tolerance band, gold means ±5% and silver means ±10%. As a multiplier band, gold means ×0.1 and silver means ×0.01.
What if there is no tolerance band?
A resistor with no tolerance band has a default tolerance of ±20%.
What is the temperature coefficient band?
Only present on 6-band resistors, it indicates how much the resistance changes with temperature, expressed in parts per million per kelvin (ppm/K). For example, a brown 6th band means 100 ppm/K.
Why does my resistor measure a slightly different value?
Real resistors vary within their tolerance band. A 1 kΩ resistor with ±5% tolerance can legitimately measure anywhere between 950 Ω and 1,050 Ω.