Resistor color code calculator (4 band)
The first two bands are digits, the third is the multiplier and the fourth is the tolerance. Choose the colors in order to see the value.
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How to use it
- Enter band 1, band 2, multiplier band and tolerance band.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Value = (band 1 digit × 10 + band 2 digit) × 10^multiplier, and limits = value × (1 ± tolerance ÷ 100). Gold multiplies by 0.1 and silver by 0.01.
Example
Inputs: Band 1 = Yellow, Band 2 = Violet, Multiplier band = Red, Tolerance band = Gold ±5%. Result: Resistance: 4,700 Ω; Reading: 4.7 kΩ ±5%; Minimum value: 4,465 Ω.
Limits and caveats
- Start reading from the end nearest the bands; the tolerance band is usually gold or silver and set slightly apart.
- Brown, red and orange can look alike after heat or under poor light; confirm with a meter if unsure.
Questions about this tool
Which end do I start reading from?
From the end the bands are closest to. A gold or silver band sits at the far end and never comes first.
What does gold mean as the third band?
Multiply by 0.1, so red red gold is 2.2 Ω. Silver in that position means multiply by 0.01.
What does ±5% tolerance mean?
The real value can be up to 5% above or below the marked value. A 4.7 kΩ 5% resistor lies between 4465 and 4935 Ω.