Resistor color code converter
Type the colors (brown black red) or an SMD code (103) to get the resistance, or type ohms to get the color bands.
The nearest standard values are 4.7 kΩ (E12, 10 %) and 4.7 kΩ (E24, 5 %).
What it means
Where does that value sit?
Read the bands from the end without the gap; the gold or silver tolerance band goes last and is ignored here. “≈” means the value needs more digits than that code has.
Every unit
That resistor in every code
Learn
Three things worth knowing
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The last digit is zeros
On both bands and SMD codes the last figure counts zeros: red is ×100, so yellow violet red is 47 × 100 = 4.7 kΩ.
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Radios of the 1920s
The Radio Manufacturers Association set the color code in the 1920s so tiny parts could be read from any side. The E12 series of standard values followed in 1952.
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Reading backwards
Start from the band nearest an end, not from gold or silver. Read the wrong way, 4.7 kΩ (yellow violet red gold) would be nonsense.
Shortcuts
Popular resistance conversions
Background
About resistor codes
Through-hole resistors are too small to print on, so they carry color bands (IEC 60062): two digits and a multiplier on a 4-band resistor, three digits and a multiplier on a precision 5-band one. Black is 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9.
Surface-mount resistors print digits instead: 103 is 10 followed by three zeros, 10 kΩ; 4R7 is 4.7 Ω, with R as the decimal point.