Resistor Color Code Decoder
Decode 3, 4, 5 and 6-band resistor colour codes, or find the bands for any resistance value.
Colour bands → resistance
Band by band
Resistance → colour bands
How it works
Pick the colours you see on the resistor, left to right, and the value appears instantly. The first two bands (three on a 5- or 6-band precision resistor) are digits, the next band is the multiplier — the power of ten you multiply those digits by — and the band set slightly apart at the end is the tolerance. So brown-black-red-gold is 1, 0, × 100, ±5% = 1 kΩ ±5%, with a real value anywhere between 950 Ω and 1.05 kΩ. A sixth band gives the temperature coefficient in ppm/K. Gold and silver multipliers divide instead of multiply, which is how small values like 0.22 Ω are marked.
The second panel works the other way round: type a resistance and it shows which colours to look for, snapping to the closest combination the bands can actually express. The tool also tells you whether the value belongs to the standard E12, E24 or E96 series. Everything is calculated in your browser with plain JavaScript — no uploads, no accounts, no ads.
Frequently asked questions
How do you read resistor color bands?
Hold the resistor so the tolerance band (usually gold or silver, or the band with the wider gap before it) is on the right, then read from the left. On a 4-band resistor the first two bands are digits (black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9), the third is the multiplier (the power of ten you multiply by) and the fourth is the tolerance. On a 5- or 6-band precision resistor there are three digit bands instead of two, and a sixth band gives the temperature coefficient in ppm/K.
What color code is a 10k ohm resistor?
A 10 kΩ resistor with 4 bands is brown, black, orange, plus a tolerance band. That is brown (1), black (0), orange (× 1 000) = 10 000 Ω, with gold for ±5% or silver for ±10%. As a 5-band 1% part it is brown, black, black, red, brown: 1, 0, 0 followed by × 100. Type 10 kΩ into the reverse panel on this page and it draws the exact bands for you.
What do the gold and silver bands on a resistor mean?
It depends on their position. In the multiplier position gold means divide by 10 (× 0.1) and silver means divide by 100 (× 0.01), which is how small values such as 4.7 Ω or 0.22 Ω are marked. In the last position they are tolerance: gold is ±5% and silver is ±10%. A resistor with no tolerance band at all is assumed to be ±20%.