Generally, black, and darker-colored inks are easier to remove because they absorb a wider range of laser wavelengths. On the other hand, the hardest ink colors to remove include:

Green: Green ink is notoriously difficult to break down with laser energy. Lasers that emit wavelengths around 694 nm (Ruby lasers) or 755 nm (Alexandrite lasers) are often used for green inks, but multiple sessions might be needed.

Sky Blue / Teal: These colors can also be challenging to treat, with wavelengths around 694 nm being used.

Yellow: Yellow doesn’t absorb laser light very well and can be resistant to removal. It may fade but not always disappear completely.

Purple and Pinks: These colors might also require more sessions compared to darker inks.

Fluorescent or glow-in-the-dark inks: These special inks can be especially difficult to remove due to their unique properties.

It’s worth noting that newer tattoo removal technologies and multi-wavelength lasers are being developed to target a broader range of ink colors more effectively. However, even with the best technology, some tattoos (especially those with a mix of colors or certain resistant shades) may not be completely removed or may require numerous sessions for significant fading.

As always, it’s important to consult with a dermatologist or a specialist in tattoo removal to assess the feasibility of removal and to understand what to expect from the process.