Resistor Color Code Calculator (4/5/6 band)
Decode 4, 5 and 6-band resistor color codes into resistance and tolerance — essential for electronics projects.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
Choose each band’s color; the resistance updates automatically.
About this tool
This resistor color code calculator decodes the colored bands printed on a resistor into its resistance value and tolerance, right in your browser. Pick the number of bands (4, 5 or 6), set the color of each ring, and read off the resistance in ohms along with the tolerance and, on 6-band parts, the temperature coefficient. Everything is calculated on your own device, so nothing you select is sent to a server.
Frequently asked questions
How do I read the bands in the right order?
Hold the resistor so the group of closely spaced bands is on the left and the single band separated by a wider gap (usually gold or silver, the tolerance) is on the right. On a 4-band part the first two bands are digits, the third is the multiplier and the fourth is tolerance; 5- and 6-band parts add a third digit, and 6-band parts add a temperature-coefficient band at the far right.
What does the tolerance band tell me?
Tolerance is how far the real resistance may stray from the labeled value. A gold band means plus or minus 5 percent and silver means plus or minus 10 percent, while tighter brown (1 percent) or red (2 percent) bands are common on precision parts. For example, a 1000-ohm resistor with a gold band is only guaranteed to fall between 950 and 1050 ohms.
Is anything I select sent to a server?
No. The band colors are decoded into a resistance value entirely by code running in your browser, so nothing you choose is uploaded to or stored on any server.