Resistor Colour Code Calculator
Decode 4-band and 5-band resistor colour codes into resistance and tolerance, or find the colour bands for a given resistance value.
Runs on your device
Result
Results appear here as you type.
What it does
Read the bands from the end furthest from the gold or silver tolerance band. In decode mode, pick the colours; in encode mode, type a value like 4.7k to get the bands.
How to use it
- Choose decode or encode, and 4 or 5 bands.
- Pick colours or type the resistance.
- Read the result.
Example
Yellow-violet-red-gold = 4.7 kΩ ±5%. Select Try an example above to see it.
When it helps
- Identifying resistors in a lab kit.
- Checking parts before soldering.
- Learning the colour code.
Questions
Which end do I start from?
The tolerance band (often gold or silver) is usually separated by a gap; start reading from the other end.
What does a missing tolerance band mean?
A 3-band resistor has ±20% tolerance. Enter it as 4 bands with tolerance "none".
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