Fraxel is a fractional laser, meaning it delivers thousands of tiny laser beams into the skin in a grid pattern rather than treating the entire surface at once. The most widely used version, the Fraxel Dual, combines two non-ablative wavelengths (1550 nm and 1927 nm) in a single device, while the Fraxel re:pair uses an ablative CO2 laser at 10,600 nm. Understanding these distinctions helps clarify what Fraxel actually does to skin and how it differs from other laser treatments.
What “Fractional” Actually Means
Traditional laser resurfacing treats every square millimeter of skin in the target area, which is effective but requires significant healing time. Fraxel pioneered a different approach called fractional photothermolysis. Instead of blanketing the skin, the device delivers 125 to 250 microscopic laser beams per pulse, creating thousands of tiny columns of treated tissue called microthermal treatment zones (MTZs). Within each square centimeter, 1,000 to 2,000 of these columns penetrate the skin while the tissue between them stays completely untouched.
Those untouched cells are the key advantage. Healthy skin surrounding each MTZ acts as a reservoir for healing, dramatically shortening recovery compared to full-surface resurfacing. Inside each treatment column, old pigmented cells in the outer skin layer are expelled, and heat delivered to the deeper layer triggers collagen remodeling and new collagen production. The result is skin renewal without destroying the entire surface.
The Two Wavelengths in Fraxel Dual
The Fraxel Dual, which is the version most dermatology offices use, houses two distinct laser wavelengths in one handpiece. Each targets a different depth and treats different concerns.
The 1927 nm thulium wavelength works on the superficial layers, specifically the outermost skin and the upper portion of the deeper layer just beneath it. This wavelength is particularly effective for pigment problems: freckles, age spots, sun damage, and melasma. It’s FDA-cleared for actinic keratosis (rough, precancerous patches from sun exposure) and various pigmented lesions.
The 1550 nm erbium wavelength penetrates deeper into the skin’s structural layer, where collagen lives. This makes it better suited for fine lines, wrinkles, acne scars, and surgical scars. It’s also FDA-cleared for skin resurfacing and treatment of periorbital wrinkles (the lines around your eyes). Practitioners can use one wavelength or both in a single session depending on what your skin needs.
Fraxel re:pair: The Ablative Option
Fraxel re:pair is a fundamentally different laser. It uses a CO2 (carbon dioxide) laser at 10,600 nm, which is ablative. That means it vaporizes thin layers of skin rather than just heating them. It’s still fractional, so it creates the same grid of treatment columns with healthy tissue in between, but the intensity is significantly greater. The manufacturer markets it as delivering the effectiveness of conventional full-surface CO2 lasers without the same prolonged downtime.
This version is reserved for moderate to severe sun damage, deeper wrinkles, and more significant scarring. Recovery takes longer, side effects are more likely, and the risk of scarring is slightly higher than with the non-ablative Dual. People with darker skin tones face a higher risk of lasting pigment changes with ablative treatment, so this version requires careful patient selection.
Non-Ablative vs. Ablative: Why It Matters
The distinction between Fraxel Dual (non-ablative) and Fraxel re:pair (ablative) is the most important thing to understand when comparing Fraxel options. Non-ablative lasers heat the deeper skin layers to stimulate collagen without removing surface tissue. Ablative lasers physically remove the outer skin. Both are fractional, but the recovery experience is very different.
With Fraxel Dual, you can expect about a week of visible healing. Immediately after treatment, skin looks intensely red and feels warm, similar to a sunburn. For the first three days, redness and swelling are prominent. Around days three to five, tiny dark dots appear on the surface as damaged cells work their way out. Significant peeling follows during days four through seven, and by the end of the first week, most flaking has stopped and makeup can be applied over any residual pinkness. Deeper collagen remodeling continues quietly beneath the surface for several more weeks.
Fraxel re:pair involves a longer inflammatory phase. Skin can look visibly inflamed for several months, and the overall healing process demands more patience and careful aftercare.
How Many Sessions You’ll Need
Fraxel Dual is typically done as a series of treatments rather than a single session. Because each pass treats only a fraction of the skin, multiple sessions are needed to cover the full treatment area with enough overlap for meaningful results.
- Mild concerns like uneven tone or faint fine lines: 1 to 3 sessions
- Moderate wrinkles or scars: 3 to 5 sessions
- Deep acne scars or significant sun damage: up to 6 sessions
- Hyperpigmentation alone: often just 1 to 2 sessions
Sessions are typically spaced about four weeks apart to allow full healing between treatments. Fraxel re:pair, because it’s more aggressive, often requires fewer sessions to achieve comparable results, sometimes just one or two.
How Fraxel Compares to Other Lasers
Fraxel isn’t the only fractional laser on the market. The technology it pioneered has become a category, and devices from other manufacturers use similar principles. What sets Fraxel apart is less about the underlying physics and more about the specific engineering: the combination of two wavelengths in the Dual handpiece, the density and pattern of the MTZs, and the particular energy levels the device delivers.
If you’re comparing options, the key questions are whether the laser is fractional or full-surface, ablative or non-ablative, and what wavelength it uses. Fraxel Dual sits in the fractional non-ablative category, making it a middle-ground treatment that delivers real results (collagen remodeling, pigment clearance, scar improvement) with roughly one week of social downtime. That positioning between gentle, no-downtime treatments and aggressive surgical resurfacing is largely why it became one of the most recognized names in cosmetic dermatology.