Resistor colour code calculator
Choose the colour bands on a resistor and read off its value and tolerance.
About this calculator
Pick 4 or 5 bands, then choose each colour. The first bands give the digits, the next is the multiplier and the last is the tolerance.
The result shows the value and the lowest and highest the resistor could really be.
Measurements and terms explained
- Digit bands
- The first two (or three) colours give the number, for example brown black = 10.
- Multiplier
- The next band says what to multiply the digits by, for example red means × 100.
- Tolerance
- How far the real value can differ, such as ±5% for gold.
- Ohm (Ω)
- The unit of resistance. 1 kΩ = 1,000 Ω and 1 MΩ = 1,000,000 Ω.
Common questions
Which end do I start from?
Start from the end where the bands are closest together. The tolerance band, often gold or silver, is at the other end.
What is a 4-band resistor?
Two digit bands, one multiplier and one tolerance band.
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