A Thorough Image-Based Comparison of Sofwave and XERF (With Case Studies) | How to Choose and Who They Suit

Sofwave is an ultrasound device developed by Sofwave Medical in Israel. Its proprietary “SUPERB™” technology simultaneously delivers seven ultrasound beams directly to the mid-dermis, an area that was difficult to treat with conventional methods, encouraging the production of collagen and elastin. The treatment aims to tighten the skin and improve firmness.
Because the skin’s surface can be cooled during treatment, it is also characterized by its ability to help minimize damage to the skin surface. In addition to FDA approval, it received approval from Japan’s Ministry of Health, Labour and Welfare in 2025.
For more details about Sofwave, please see the following article.

XERF is a monopolar RF (radiofrequency) device developed in South Korea. It features the world’s first dual-frequency system (6.78 MHz + 2 MHz), allowing thermal energy to be delivered efficiently from the dermis to the fat layer.
By using its three irradiation modes according to the treatment objective, XERF can address a wide range of concerns, from improving skin firmness to tightening the facial contour. Its proprietary cooling function allows treatment while helping to reduce pain and downtime. The device has received approval from the Korean MFDS.
For more details about XERF, please see the following article.

The fundamental difference between the two treatments lies in the type of energy they use. Sofwave uses “ultrasound,” while XERF uses “radiofrequency (RF).” This difference affects everything from how heat is delivered to the direction of the effects.

In simple terms, ultrasound focuses heat and delivers it intensively to a specific depth, while radiofrequency heats a broad area through frictional heat generated by electrical resistance in the tissue.

We will explain each of the two fundamental differences in detail.

Sofwave’s SUPERB™ technology uses seven transducers operating simultaneously to deliver cylindrical ultrasound energy evenly to the dermis. Unlike HIFU, which builds up point-like energy, it can heat a broad area in a plane. This allows it to treat, in a single shot, both the shallow layer effective for improving wrinkles (0.5–1.5 mm) and the deeper layer effective for improving sagging (1.5–2.0 mm).

XERF is a device that combines two types of radiofrequency for treatment. The 6.78 MHz frequency concentrates energy in the dermis to superficial layers, promoting collagen contraction and production. The 2 MHz frequency has properties that allow it to penetrate physically deeper and is responsible for heating the deep fat layer. Combining these two frequencies makes it possible to deliver heat at low output to deeper areas that could not be reached with a single frequency.

Sofwave is a treatment that specializes in “powerful tightening of the dermis.” Concentrating a large amount of heat on dermal collagen produces both immediate contraction and long-term collagen production. Its ability to treat thin-skinned areas such as the neck and around the eyes, as well as people with little fat, is a feature not found in other devices.

XERF, on the other hand, specializes in “wide-area tightening extending to deep layers.” Its three modes allow treatment to be adjusted according to the thickness of fat and depth of sagging in each area, making it effective for fat-related sagging such as changes in the facial contour and double chin.

Rather than asking which is superior, it is important to choose the treatment that matches the “depth” and “cause” of your sagging in order to achieve results.

Even though both are treatments for sagging skin, Sofwave and XERF are suited to different concerns. Here, we organize the direction of their effects and when you can expect to notice them.

Sofwave is positioned as a treatment that “enhances skin texture.” Because it specializes in dermal collagen production and contraction, people with the following concerns may be more likely to notice results.

All of these concerns are associated with a reduction in collagen in the dermis. Rather than producing a major change in the facial contour, Sofwave creates a sensation closer to the skin becoming tighter, as if lifted from within. The fact that it can also be performed on people with a slim build or little facial fat is a strength not found in many other devices for treating sagging skin.

XERF is a treatment that “tightens deep tissues, including the fat layer.” Frictional heat from radiofrequency penetrates a broad area and produces a tightening effect on sagging caused by the descent of fat. It is particularly expected to be effective for the following types of sagging of subcutaneous tissue and fat-related changes.

The three modes allow adjustments close to a customized treatment. For example, Shallow + Middle can be combined when someone wants to improve skin quality while also slimming the facial contour. XERF is suited to people with a relatively larger amount of fat or those seeking a change in facial contour.

Because collagen production requires a certain amount of time, Sofwave often produces changes that are felt more strongly after one to two months than immediately after treatment. With XERF, the effects of fat and tissue contraction tend to appear relatively sooner. Neither treatment produces permanent effects, and combining treatment with regular maintenance can help maintain the results.

Before undergoing treatment, it is important to understand the pain and downtime involved. Both treatments have little downtime, but the sensations during treatment differ. Let’s take a closer look at each one.

Sofwave is designed to minimize pain compared with HIFU because it delivers energy while cooling the skin’s surface. However, because it concentrates strong energy in the superficial dermis, it may cause a prickling sensation or mild warmth. Some clinics may use topical anesthesia, so it is reassuring to confirm how pain is managed before treatment.

There is almost no downtime, and redness subsides within several hours for most people. Makeup is often possible from the day of treatment, so the impact on daily life is limited.

XERF significantly reduces pain compared with conventional radiofrequency devices through its “Wave Fit Pulse” technology and cooling system. Many people do not require anesthesia, and the sensation during treatment is generally described as a gentle warmth. Sensations vary from person to person depending on the treatment area and power settings.

Temporary redness or warmth may occur after treatment, but these symptoms usually subside within several hours to the following day. XERF is considered a treatment with little impact on returning to work or other daily activities.

When the two concerns of “wanting to restore skin firmness” and “wanting to tighten the facial contour” overlap, combination treatment with Sofwave and XERF may be considered. Combining ultrasound (Sofwave) to increase dermal collagen with radiofrequency (XERF) to tighten tissue including the fat layer may provide complementary effects, with less interference because each treatment works on a different layer.

However, because there are risks associated with layering multiple treatments on the same area, this should be performed under the judgment of the treating physician. At LIVELY CLINIC, we also offer consultations for combination treatment plans tailored to your skin condition. Please feel free to consult us.

In addition to comparing Sofwave and XERF, we will also clarify how HIFU, Thermage, and Volnewmer—which are often considered as options for treating sagging skin—fit into the range of treatments available.

HIFU uses high-intensity focused ultrasound to deliver heat at multiple depths, from the superficial dermis to the SMAS fascia (up to approximately 4.5 mm). Because it can approach the level of the fascia, it is particularly suited to cases where the goal is to physically lift the facial contour.

Sofwave also uses ultrasound, but its treatment depth is specialized at 1.5 mm in the dermis and it does not approach the fascia as HIFU does. As a general approach, HIFU is used when you want to “lift the foundation from a deeper layer,” while Sofwave is used when you want to “improve skin quality by increasing dermal collagen.”

Thermage is a treatment for sagging that uses monopolar RF (radiofrequency) to heat tissue approximately 3 mm beneath the skin. Like XERF, it is an RF-based treatment, but it does not have an adjustment function for deeper tissue like XERF’s dual-frequency system. Thermage is considered particularly effective for tightening the entire face and creating a slimmer-looking facial contour, making it suitable for people who want to define their facial line.

Sofwave targets a shallower layer than Thermage—the dermis—and its effect on the dermis for improving wrinkles and tightening the skin is considered stronger than that of other devices. The treatments are generally differentiated as follows: Sofwave for “tightening the skin’s surface and improving wrinkles,” and Thermage for “tightening the face and making it look smaller.”

Volnewmer uses radiofrequency (RF) and works on the dermis to superficial fat layer. Like XERF, it is an RF-based treatment, and one of its features is that results can be felt relatively soon after treatment—generally within two weeks to one month. Compared with Sofwave, Volnewmer works on a somewhat deeper layer, extending to the superficial fat, while Sofwave has a stronger effect on the dermis.

Sofwave uses a higher treatment temperature, and its tightening effect tends to be stronger. On the other hand, Volnewmer is considered suitable for people with descended fat or softer skin. Sofwave is effective at creating a tightening sensation in which “the skin seems to adhere closely to the underlying bone structure,” and is particularly suited to people concerned about excess or lax skin.

Based on the points discussed so far, here are the main considerations for choosing between them. This section focuses on the question, “I understand how they work, but which one is right for me?”

Sofwave is suitable for people whose main concerns are changes in skin quality, such as reduced firmness or elasticity, visible pores, and fine lines. Because it is a treatment that promotes substantial dermal collagen regeneration, it is suited to people seeking a change that feels more like “younger-looking skin” than a change in facial contour.

It is also suitable for people with a slim build, little facial fat, or concerns about hollowing of the cheeks. Unlike treatments such as HIFU and XERF that work on deep fat, Sofwave does not raise concerns about treatment-related fat atrophy.

Another feature not found in some other treatments is that it can also address wrinkles and sagging in thin-skinned areas such as the neck and around the eyes. It is also a practical option for people who want to minimize pain and downtime.

XERF is suitable for people concerned about sagging caused by descended fat, such as a heavy or undefined facial contour and a double chin. Because the irradiation depth can be customized using three modes, a more precise approach is possible when the treatment is performed after determining which layer is causing the sagging.

It is also suitable for people who want to improve not only skin quality but also their facial contour, or who want to feel the effects relatively soon after treatment. Although it is not as effective as HIFU for deep lifting, heating a broad area from the fat layer to the dermis may produce a natural change in facial contour.

Both Sofwave and XERF can produce noticeable results only when the treatment is selected to match the “depth” and “cause” of your sagging. However, many aspects of your skin condition cannot be assessed without an examination, and simply choosing a device whose name you happen to recognize may not produce the results you expect.

At LIVELY CLINIC, we offer both Sofwave and XERF and can propose an appropriate treatment plan based on your current skin condition. During a consultation with a physician, we will explain carefully whether one treatment or a combination is needed. If you are unsure which treatment is right for you, please feel free to consult us.

Both Sofwave and XERF are treatments that improve sagging without incisions, but they differ in how they work, their effects, and the concerns they are suited to.

Sofwave concentrates heat at a depth of 1.5 mm in the dermis to regenerate collagen, making it particularly suited to improving skin quality, wrinkles, and firmness. XERF heats the dermis through the fat layer in three stages, making it suitable for tightening the facial contour and addressing sagging caused by fat.

It is also useful to understand the different roles of other treatments: HIFU provides a deep lift reaching the fascia, Thermage focuses on facial contour tightening, and Volnewmer improves firmness, including in the superficial fat layer. This can help you make a more precise choice. For any of these treatments, choosing based on the cause of your concern rather than the device name is a shortcut to achieving results. We recommend receiving an examination at a clinic before making a specific decision.