Both of these are fractional lasers — they treat thousands of tiny columns and leave the skin in between untouched, which is what makes recovery survivable at all.
The difference is what happens inside those columns. CO2 removes the tissue entirely. Fraxel heats it and leaves it in place.
Everything else about these two — results, recovery, risk, cost — follows from that one distinction.
Both dominate the dermis row — this is collagen remodelling in both cases. The divergence is on the barrier row, and it is the entire story: CO2 removes the columns it treats, which is why it delivers more and why recovery is measured in weeks. Fraxel heats and leaves them, trading some depth for a barrier that stays intact. Fraxel edges ahead on pigment; CO2 is the one that can also cause pigment problems.
Deep acne scars | Fractional CO2 | Strong
The long-standing benchmark. Removing tissue produces the most remodelling. Fraxel helps moderate scars but is outmatched on deep ones.
Deep wrinkles | Fractional CO2 | Strong
Etched lines around the mouth and eyes respond better to actual resurfacing.
Brown spots and sun damage | Fraxel | Strong
This is where Fraxel excels, especially the 1927nm wavelength, and it does so without the recovery CO2 demands.
Overall texture and tone | Fraxel | Moderate
A series of gentler sessions handles general texture well and lets you keep living your life in between.
Downtime | Fraxel | Consensus
Three to five days of redness and roughness, versus 7–14 days of raw, weeping, peeling skin. This is the deciding factor for most people.
Number of sessions | Fractional CO2 | —
Often one to three, versus three to five for Fraxel. CO2 concentrates the commitment; Fraxel spreads it out.
Skin of color | Fraxel, conservatively | Moderate
This is the most important safety point on the page. CO2 carries the highest risk of causing dark marks of any resurfacing option, and many specialists avoid it entirely on deeper tones. Fraxel is usable with conservative settings and priming, but it is still heat, and it still requires an operator experienced with your skin type. Neither is a casual decision here — ask directly how many patients with your skin tone the clinic has treated.
Cost per session | Fraxel | —
Lower per session, but you need more of them, so total cost can end up similar.
Risk of complications | Fraxel | Consensus
CO2 carries higher risks of prolonged redness, infection, scarring, and pigment change. It is a bigger procedure and deserves to be treated as one.
Pick one for a given course. They are not layered in the same session.
Choose CO2 if: you have deep scarring or deep wrinkles, you can genuinely take 1–2 weeks of visible recovery, and your skin tone and history make you a reasonable candidate.
Choose Fraxel if: your concerns are sun damage, brown spots, and moderate texture; you cannot take extended downtime; or you have a deeper skin tone and want the lower-risk path.
Sequencing is common. Some people do a CO2 course for scars, then maintain with occasional lighter treatments years later.
Non-negotiable afterward: strict sun avoidance and daily sunscreen for weeks. The single most common cause of a bad result is sun exposure on healing skin.
Ask about priming. For anyone at risk of pigment change, a topical routine for several weeks before treatment meaningfully lowers that risk. A clinic that does not raise this on its own is worth questioning.
Get a test spot if you have any doubt about how your skin will respond. It costs one small area and can save a face.