The wavelengths of the colors of the rainbow range from 390 nanometers to 780 nanometers. There are wavelengths that are lower or higher than those in the visible spectrum, and several types of radiation are simply light waves with other wavelengths.
The wavelength of red falls between 622 and 780 nanometers, while that for orange is 597 to 622 nanometers. The wavelength for yellow is 577 to 597 nanometers. The wavelength for green is 492 to 577 nanometers. The color wavelength for blue is 455 to 492 nanometers. The wavelength for violet is 390 to 455 nanometers.
X-rays and ultraviolet light have wavelengths shorter than violet light, so they are not visible. Infrared and radio waves have wavelengths longer than red light, which means they are also not in the visible spectrum.