The type of light with the highest frequencies in the entire electromagnetic spectrum is gamma rays. If the question is restricted to just visible light, then violet light has the highest frequency.

Quick scoop

  • Across all electromagnetic waves:
    • Gamma rays have the shortest wavelengths and therefore the highest frequencies and energies.
* They lie beyond X‑rays on the high‑energy end of the spectrum.
  • Within visible light only:
    • Violet light sits at the high‑frequency end of the visible spectrum, around 380–450 nanometers in wavelength, and has the greatest energy of the visible colors.
* Red light is at the opposite end, with the **lowest** frequency and longest visible wavelength.

So:

  • Highest frequency overall: gamma rays.
  • Highest frequency visible to human eyes: violet light.

Information gathered from public forums or data available on the internet and portrayed here.