Resistors are color-coded to indicate their resistance value and tolerance, using a system of colored bands that can be confusing for beginners and time-consuming to look up for experienced engineers alike. This resistor color code calculator decodes the color bands on a resistor to instantly reveal its resistance value in ohms and its tolerance percentage. It works for both 4-band and 5-band resistors, the most common types used in electronics projects. Whether you're a hobbyist building a circuit, an electronics student learning the color code system, or a professional needing a quick reference, this tool eliminates the need to memorize or look up color code charts.