Ask anyone who works in removal what people want to know first, and it’s always the same question: how many sessions is this going to take? The honest answer has always been “it depends,” which is true but not especially satisfying, so it helps that a study published in 2025 in the Journal of Cosmetic Dermatology finally gives that answer some real structure and spells out what it actually depends on.

The study, in plain terms

Researchers at a Swiss clinic followed 116 patients with black tattoos all the way through to complete clearance using a picosecond laser, tracking everything they could about each tattoo and each person before working out which factors actually predicted the number of sessions. The result is a model they named after themselves, the Smarrito-Pineau model, and its headline finding is simple enough: the average tattoo took 6 sessions, with a range running from 2 to 20. The right mental picture, in other words, is several visits spaced out over months rather than anything close to one-and-done.

What actually drives the number

This is the part we found most useful, because a few things move the needle quite a lot while a few others that people assume matter turned out not to.

  • Ink density is by far the biggest factor. Lightly inked tattoos averaged about 3.2 sessions while densely packed ones averaged around 9.0, simply because heavier, more saturated ink takes more passes to clear.
  • Location mattered more than we’d expected. Tattoos on the upper trunk cleared fastest at roughly 4.3 sessions on average while hands and fingers took the longest at around 7.8, which tracks with circulation, since areas with a richer blood and lymph supply flush the broken-down ink away faster.
  • The age of the tattoo plays a role too. Very fresh tattoos under about 10 days old and quite old ones over 5 years tended to need fewer sessions while the in-between years needed more, though treating a brand-new tattoo is a case-by-case call based on skin condition rather than something to assume.
  • Technique counts as well, with dotwork and shading coming off more easily at around 4.4 sessions than line work or mixed styles at around 7.

What surprisingly didn’t matter much

A couple of these caught us off guard, because several of the things people tend to worry about had little to no effect on the session count at all, including the overall size of the tattoo, the patient’s age and gender, their skin type within the range studied, and whether the tattoo was lettering or a drawing. The upshot is that a big tattoo isn’t automatically a longer project, since a small but densely packed one can take just as much work.

The honest fine print

It’s worth keeping the limits in view, because this model was built on black tattoos only, at a single clinic, with 116 people, using a picosecond laser, and it excluded the darkest skin tones (Fitzpatrick V to VI) since the 755nm laser used isn’t suited to them. Colored ink is a separate and generally harder story, and the researchers note that complications do show up in a small share of cases, all of which makes this an excellent framework for setting expectations rather than a guarantee. Your provider’s in-person assessment of your specific tattoo still has the final say.

None of this is at odds with the broader guidance. The FDA notes that laser removal takes several treatments spaced a few weeks apart, with the exact number depending on things like the tattoo’s size and color, and it cautions that complete removal isn’t always possible.

The practical takeaway is that if you want to guess your own number before you ever sit down with a provider, you should look first at how dense and saturated the ink is and then at where it sits on your body, because those two factors tell you most of what you need to know.

A note on this guide

Tattoo Takeoff is an independent, research-based resource. It is not a clinic and does not perform removal, and nothing here is medical advice. A qualified provider’s in-person assessment is the only way to estimate the number of sessions your specific tattoo will need.

Sources

Last reviewed: June 21,2026. Updated as we learn more.