My skin truly did look lit from within for several days
In the long human search for ways to hold back time's mark on the body, a South Korean radio-frequency device called XERF has arrived in American dermatology offices carrying something rarer than buzz: credible results. By using two electromagnetic frequencies simultaneously — a first among skin-tightening technologies — it reaches collagen and elastin across multiple layers of skin, offering both deep lift and surface renewal without surgery, pain, or recovery. For those with mild to moderate laxity, it represents not a miracle but a meaningful step forward in a field long crowded with overpromise.
- A beauty editor who had tried every major skin-tightening device without visible results booked a XERF session expecting nothing — and walked away with a genuinely lifted jawline.
- Kim Kardashian's Instagram endorsement ignited demand almost overnight, while prominent dermatologists publicly questioned whether the hype outpaced the science.
- Unlike all previous radio-frequency devices, XERF deploys two frequencies at once — 6.78MHz and 2MHz — allowing it to stimulate collagen and elastin at both deep and superficial skin layers simultaneously.
- The treatment feels like a hot-stone massage, causes no redness, and requires zero downtime, making it unusually accessible for patients who cannot afford recovery time.
- Full results emerge slowly over three months, and the device is best suited for early-stage sagging rather than severe laxity — a meaningful distinction that separates realistic candidates from those who may still need surgery.
After years of submitting to every major skin-tightening device — Ulthera, Thermage, Morpheus8, and more — a beauty editor had grown accustomed to modest glows and no real change in contour. When three friends texted about XERF in a single week, she booked an appointment expecting the usual pleasant hour and nothing transformative. Instead, something actually worked.
XERF is a radio-frequency device from South Korean company Cynosure Lutronic that entered American dermatology practices last year. Its viral moment was partly ignited by Kim Kardashian calling it her "new fave" on Instagram, which drew both demand and skepticism. Dermatologist Shereene Idriss questioned whether its popularity owed more to marketing than results; Dr. Paul Jarrod Frank cautioned against expecting surgical outcomes. But practitioners using it regularly report genuine enthusiasm — dermatologist Michelle Henry called it her most popular treatment after nearly a year of use.
What sets XERF apart is its use of dual radio frequencies — 6.78MHz and 2MHz — making it the first RF device to operate on two frequencies simultaneously. Every competing device uses only one. This allows XERF to stimulate fibroblasts across multiple skin layers, boosting both collagen and elastin production for deep lifting and surface tightening together. Dermatologist David Kim tested it on half his face in Seoul before bringing it to his New York practice and observed a difference that persisted for months.
The experience itself is disarmingly gentle. With cooling technology built into the wand, the treatment feels like a hot-stone massage — no burning, no tears, even on sensitive areas. A full face and neck session takes about an hour, and patients walk out with no redness, no downtime, and no restrictions. The device is best suited for mild to moderate laxity: early jawline softening, neck looseness, fine lines. Those with severe sagging may still require surgery.
Full collagen remodeling takes roughly three months, but an immediate short-term contraction is visible right after treatment. Three weeks after her session, the editor's jawline remained genuinely tighter — particularly where soft jowls had begun to form — and her skin appeared fresher and bouncier overall. A second treatment is recommended at three months, followed by annual maintenance. She is still waiting to see what the full timeline delivers.
I have spent years in the beauty editor's chair submitting to every skin-tightening device that exists. Ulthera, Sofwave, Thermage, Morpheus8, Clear + Brilliant, Fraxel, EmSculpt—the list goes on, some forgotten entirely. A few made my skin brighter. None made it noticeably tighter or more contoured. So when I booked a XERF appointment, I expected the usual: a pleasant hour, a modest glow, nothing transformative. Instead, something actually worked.
XERF is a radio-frequency device made by South Korean company Cynosure Lutronic that landed in American dermatology offices last year. I'd never heard of it until three friends texted me about it in a single week. The catalyst was Kim Kardashian calling it her "new fave" on Instagram. Suddenly everyone wanted access. Not everyone was convinced. Dermatologist Shereene Idriss published a Substack questioning whether XERF's viral moment owed more to the company's marketing budget than to actual results. Dr. Paul Jarrod Frank posted a warning video cautioning people against expecting a surgical face-lift outcome. But practitioners who've been using XERF regularly report being genuinely impressed.
I went to dermatologist Michelle Henry, who has treated patients with XERF for nearly a year. "I've used every variation of radio-frequency device, and XERF really stands out," she told me. "Patients love it so much it's become my most popular treatment." The device works by using electromagnetic waves to generate heat, which triggers fibroblasts to produce more collagen and elastin. During treatment, a grounding pad sits on your back while conductive gel covers the target area. What makes XERF different from older radio-frequency machines like Thermage—which have been around since the early 2000s—is that it's the first RF device to use dual frequencies: 6.78MHz and 2MHz. Every other RF-based lifting device uses only one. Dermatologist David Kim, who tested XERF in Seoul before bringing it to his New York practice, treated half his face to evaluate it. He saw a significant difference that persisted for months.
The dual frequencies let XERF reach collagen and elastin across multiple skin layers, delivering both deep-tissue lifting and surface tightening. Think of elastin as a rubber band, explains dermatologist Sapna Palep, co-founder of the soon-to-open Journelle Skin clinic in New York. You lose it naturally with age, but stimulating production restores that "stretch back" quality that tightens skin. The collagen boost fills in dips and bumps, making skin appear firmer overall. This differs from ultrasound-based treatments like Ultherapy and Sofwave, which use high-intensity focused ultrasound instead of radio frequency. Ultherapy can deliver dramatic lift, especially for neck and chin laxity, but it's brutally painful—I required Percocet and Valium and barely survived my own session. Sofwave is shallower and gentler but may yield subtler results.
XERF feels like a hot-stone massage. The machine has cooling technology that prevents your skin from ever feeling burned. As Dr. Henry moved the wand across my face, she warned me it might feel "pinchy" as heat built up. It never did, even on my thin forehead, which usually makes me tear up during treatments. The full face and neck took about an hour and felt deeply relaxing. Afterward: no downtime. You can wear makeup, exercise, work—immediately. Most people don't even redden. Dr. Henry does XERF frequently for brides who want a glow even if full results won't arrive by wedding day.
XERF works best for people with mild to moderate skin laxity—early jawline sag, neck looseness, fine lines, collagen loss. Anyone with severe sagging or deep wrinkles may need surgery instead. Collagen builds slowly, so full results appear around three months post-treatment. But there's an immediate effect. After treating one side of my face, Dr. Henry showed me my jawline in a mirror. It looked lifted—a short-term contraction that would last a few days. The skin also glowed intensely. Three weeks later, that radiance has faded, but my jawline is genuinely tighter, particularly where I'd started developing soft jowls below my mouth corners. My skin looks fresher and bouncier. The recommendation is a second treatment after three months, then annual maintenance. I'm waiting to see what three months brings.
Notable Quotes
I've used every variation of radio-frequency device, and XERF really stands out. Patients love it so much it's become the most popular treatment in my practice.— Dr. Michelle Henry, dermatologist
It's the first RF device in the world to use dual frequencies. All other RF-based lifting devices use only one frequency.— Dr. David Kim, dermatologist
The Hearth Conversation Another angle on the story
Why did this one actually work when so many others didn't?
It's the dual frequencies. Most radio-frequency devices use one wavelength. XERF uses two, so it's reaching deeper layers and surface layers at the same time. You're not just stimulating collagen in one zone—you're hitting elastin and collagen across the whole thickness of skin.
But Ultherapy has been around forever and people swear by it.
Ultherapy is powerful, but it's also brutal. I needed sedatives to get through mine. XERF is comfortable—it actually feels good. That matters when you're asking people to come back for maintenance treatments.
The Kardashian effect seems to have created some skepticism among doctors.
Fair skepticism. One dermatologist basically said the hype might be marketing, not science. But the doctors actually using it regularly aren't paid influencers—they're saying it's genuinely their most popular treatment now. That's different from a one-off celebrity endorsement.
How long until you know if it really worked?
Three months for full results. But I saw a difference immediately—my jawline tightened within hours. That faded after a few days, but the underlying tightness stayed. It's like the device woke something up in the skin.
Is this a one-time thing or do you need to keep doing it?
Maintenance. One treatment now, another in three months, then once a year after that. It's not a permanent fix—it's more like going to the gym for your skin.
Who shouldn't get it?
Anyone with severe sagging or deep wrinkles. XERF is for early signs of looseness, not for replacing a face-lift. If your skin is already significantly compromised, you need surgery.