Resistor Color Code Calculator
Decode resistor color bands to find the resistance value. Select the colors for each band and the calculator shows the resistance, tolerance and acceptable range.
Select band colors or enter resistance value directly.
How It Works & Formula
For a 4-band resistor, value = (band1 x 10 + band2) x multiplier, and the tolerance band gives the percentage range of the value.
Frequently Asked Questions
How do I read resistor color bands?
Read the bands from left to right. The first two bands are digits, the third is the multiplier, and the fourth is tolerance.
What does the gold tolerance band mean?
A gold band indicates a 5% tolerance, meaning the actual value can vary by plus or minus 5%.
What about 5-band resistors?
This calculator supports the common 4-band resistor type used in most hobby and educational projects.