What is the frequency of light with a wavelength of NM?

All light travels in the speed of light in vacuum, that is 300,000 km/sec. The relevant formula is C = f*lambda, where C is the speed of light, f is the frequency and lambda the wavelength. Therfore, f = C/lambda. Here lambda = 632.8nm, so f = 4.741E14 or 474 terahertz.

The color of this light, incidentally, is red. Please see the links. They are beautiful, anyway.