- Donna Mills
- Published 8 Sept 2026
- Last Modified 2 Nov 2026
- 5 min
Resistor Colour Code Calculator
Use our Resistor Colour Code Calculator to help you determine the resistance value to match your requirements
It can be difficult to calculate the tolerance or resistance value of a resistor, especially if you’re working quickly or the colours of the bands have faded. With our resistor colour code calculator, you can get the answer you need in seconds, and without the risk of human error.
Simply select the colours from your resistor (whether it’s a 4-band, 5-band, or 6-band resistor), and the calculator will instantly display the resistance value in ohms.
What is a Resistor Colour Code?
The resistor colour code is a standardised system of colour bands printed on resistors which are used to indicate the resistance value, tolerance and occasionally the temperature coefficient of the resistor. Sometimes written labels can be too small to print on tiny components, making resistor colour coding difficult to interpret, so this method helps to identify these specifications a lot easier.
Resistor Colour Code Table
Colour | 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% |
Whether you're prototyping a new circuit, repairing existing hardware, or designing systems with stepper motors, DC motors, servo motors, or brushless electric motors, having accurate resistor values is essential. Proper resistance ensures your components operate within safe limits and that your motor controllers and other electronics perform reliably. Our Resistor Colour Code Calculator is a must-have for anyone working with electronic components, designed to save time, reduce errors, and support both beginners and professionals in electronics.
Browse some of our key product ranges and related content below.
Through-hole Resistors
Through-hole resistors are an example of a typical passive component that is too small to have numerical labels printed on them and thus benefit from colour coding. They are used to reduce the flow of electrical current in a circuit.
Breadboards
Breadboards are a type of solderless plugboard which is used for prototyping. The resistor colour code is essential for working with breadboards to quickly and accurately determine resistor values.
Digital Multimeters
Digital multimeters are used to measure resistor values electrically and are often used in conjunction with the resistor colour code system to ensure accuracy.
Donna is a Senior SEO Specialist at RS, specialising in the creation and optimisation of industry-led content. Passionate about connecting audiences with valuable information, she develops a wide range of resources, including industry insights and engineering calculators, designed to help professionals solve real-world challenges. At the weekend you might catch her in her Volkswagen Campervan, enjoying musical theatre, reading, and spending time with family and friends.