Resistor Color Code Calculator (Bands ⇄ Value)
Pick the color bands of a 4-, 5- or 6-band resistor to get its resistance, tolerance, temperature coefficient and tolerance range. Or type a resistance to see the bands and the nearest standard value in E6 to E192. Everything runs in your browser and nothing is sent to a server.
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Common settings
Read a resistor from its color bands
Choose the colors from the left, with the gold or silver tolerance band on the right.
Result
Find color bands from a resistance
Accepts 4.7k, 4k7, 2.2M, R47 or 470 (in ohms; the Ω sign is optional).
Color bands
How to use
- Choose 4, 5 or 6 bands under "Number of bands".
- Under "Read a resistor from its color bands", pick the colors from the leftmost band.
- Under "Find color bands from a resistance", type a value such as 4.7k or 4k7 into "Resistance".
- Pick an "E series" to see the nearest standard value and its neighbors.
Notes
- Read with the gold or silver tolerance band on the right; the first band is the one closest to the opposite end. If the orientation is unclear, measure the resistor with a multimeter.
- 4-band resistors carry 2 significant digits and 5- or 6-band resistors carry 3. A 3-digit value such as 4.75 kΩ cannot be shown with 4 bands.
- Temperature coefficient colors differ between standards and manufacturers (this tool uses a table where black is 250 ppm/°C). Check the datasheet for critical designs.
- E48, E96 and E192 are calculated and rounded to 3 digits, so a few values may differ by one digit from the published tables. E6, E12 and E24 use the standard tables.
- Colors shift with age and lighting. Brown and red, orange and red, or gray and white are easy to confuse, so measure when in doubt.
Glossary
E series
A set of preferred values for resistors and capacitors. One decade is split geometrically, giving 12 values for E12 and 96 for E96. Higher numbers are finer and suit tighter-tolerance parts.
Tolerance
The allowed deviation from the nominal resistance. A 4.7 kΩ resistor at ±5% falls anywhere from 4.465 kΩ to 4.935 kΩ.
Temperature coefficient
How much the resistance changes per degree Celsius, in ppm/°C (parts per million). On a 6-band resistor, the sixth band shows it.
FAQ
What is the difference between 4-band and 5-band resistors?
A 4-band resistor has two digits, a multiplier and a tolerance band; a 5-band resistor has three digits, a multiplier and a tolerance band. 5-band parts are common for precision resistors (±1% and tighter). A 6-band resistor adds a temperature coefficient band.
Which end do I start reading from?
Hold the resistor with the gold or silver tolerance band on the right and read from the left. The tolerance band is often spaced slightly apart from the others, and the first band is at the opposite end. If it is unclear, measure with a multimeter.
What happens when gold or silver is the multiplier?
Gold means ×0.1 and silver means ×0.01. For example green, blue, gold, gold is 56 × 0.1 = 5.6 Ω at ±5%. This is how resistors below 10 Ω are marked.
Why does it say my resistance cannot be shown in bands?
Four-band resistors carry 2 significant digits and 5- or 6-band resistors carry 3. For example 4.75 kΩ works with 5 bands but not with 4. "Use the nearest standard value" swaps in the closest E series value.
How is the nearest E series value chosen?
The tool picks the standard value with the smallest ratio (logarithmic) distance to your input. For 4.8 kΩ in E24, 4.7 kΩ is nearest, about -2.1% away. The neighbors above and below are shown too.
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