5bandcodes

5bandcodes refers to a resistor color coding scheme that uses five colored bands to encode resistance values and tolerances. In the common five-band scheme, the first three bands are significant digits, the fourth is the multiplier, and the fifth is tolerance. Some precision resistors also carry a sixth band to indicate temperature coefficient.

Color mapping follows a standard set of rules. The digits 0 through 9 are represented by black, brown, red, orange, yellow, green, blue, violet, grey, and white respectively. For the multiplier, the same colors indicate powers of ten (10^0 to 10^9), with gold representing 0.1 and silver representing 0.01. Tolerance is indicated by color bands such as brown 1%, red 2%, green 0.5%, blue 0.25%, violet 0.1%, grey 0.05%, gold 5%, and silver 10%; in some cases, no tolerance band denotes 20%.

Reading a five-band resistor involves determining orientation and then extracting the values. The band nearest the end that is slightly separated or capped is typically the tolerance band, helping determine the correct direction to read from. The first three bands give the three digits, the fourth band gives the multiplier, and the fifth band gives the tolerance. For example, bands brown-black-red-brown-gold encode 1, 0, 2 as digits, a multiplier of 10, and a tolerance of 5%, producing a resistance of 1020 ohms (1.02 kΩ).

Uses and notes: The five-band code is common on metal film and other precision through-hole resistors, especially where 1% or tighter tolerances are required. It provides higher precision than the older four-band scheme, but correct orientation is essential to avoid errors. Some components may include a sixth band for temperature coefficient.