Resistor color code
4- or 5-band resistor value and tolerance from colors.
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About Resistor color code
Decode 4-band or 5-band resistor color codes to resistance in ohms and tolerance — offline.
Through-hole resistors still wear their value on color bands. Looking up the EIA chart every time is slow; this decoder maps band colors to digits, multiplier, and tolerance so you can read a part in seconds.
Choose 4-band or 5-band mode, set each band’s color, and read ohms plus tolerance percent. Six-band temperature-coefficient parts are not in this version — keep a chart handy for those.
Ohm’s law turns that resistance into current or voltage once you know the rest of the circuit. Geometry and scientific calculators are general math, not EIA decoders.
How to use Resistor color code
- 1Pick 4-band or 5-band.
- 2Set each band color from the selector.
- 3Read resistance and tolerance.
What it won't do
- 4- and 5-band only.
- No SMD numeric decoder on this page.
Common questions
Are 6-band resistors supported?
Not in this version. Four and five bands cover the common cases; six-band TCR needs an extended chart.
Does this work for surface-mount codes?
No — SMD parts usually use numeric codes, not color bands. This tool is for banded through-hole resistors.
Why doesn’t the value match my multimeter?
Tolerance bands allow a range, and meters have their own error. Also confirm you counted bands from the correct end (tolerance band orientation).
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