Resistor colour code calculator
Click the bands you can see and read off the value, the tolerance range and the schematic notation. Handles 4, 5 and 6 band resistors.
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Band 1 — first digitYellow
Band 2 — second digitViolet
MultiplierRed
ToleranceGold
Resistance
4.7 kΩ
Tolerance
± 5 %
Anything from 4.465 kΩ to 4.935 kΩ is in spec.
On a schematic
4k7
The letter stands in for the decimal point, so a smudge cannot turn 4.7k into 47k.
Gold and silver are never a first band — if you can see one, you are reading from the wrong end. Turn the resistor round.
Where this comes from
The number is the easy part. If you have to explain it to a panel, read the write-up — it goes through the formula, the assumptions and the mistakes that make the answer wrong.
Resistor colour codeRead any 4, 5 or 6 band resistor: the digit, multiplier and tolerance tables, which end to start from, and the SMD codes.Other calculators
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