InMode FX Results: When Does Chin Fat Shrink?

InMode results usually start to show after the 2nd or 3rd session, and fat under the chin keeps shrinking for 1 to 3 months after your last one. The tight, warm feeling on treatment day comes from heat, so it isn't a fair way to judge results.

That's why a mirror check a week after your first session can feel disappointing. Below, we'll cover what InMode FX and Forma each target, when each one tends to show change, which reactions are normal, and when to take the photos that actually tell you something.

Quick summary

• InMode results tend to appear from the 2nd or 3rd session, and fat change grows over the 1 to 3 months after your last session.

• Forma benchmark: in a study with 4 sessions 2 weeks apart under the chin, sagging scores changed after the 2nd and 3rd sessions.

• In a belly study of an FX-type device, fat volume dropped by 202.4 cc at 1 month and 428.5 cc at 3 months.

• Redness and swelling right after treatment fade, so take comparison photos at 1 and 3 months after your final session.

InMode FX vs. Forma: What Does Each One Target?

InMode FX and Forma heat different layers, which is why their results show up on different schedules. InMode is one platform with swappable handpieces, and these two are the ones most often used under the chin and along the jawline.

InMode FX warms the fat layer with radiofrequency (RF) energy and adds very short, high-voltage electrical pulses. Fat cells hit by those pulses don't melt on the spot. They break down gradually over the following weeks, so the change keeps building after your sessions are done.

Forma works higher up. It heats the dermis*, the layer just above the fat, with the goal of firmer skin and a crisper jawline. Put simply, FX is about the fat, and Forma is about the skin holding it.

*Dermis: the layer of skin under the surface, where most of your collagen sits.

When Do InMode Results Show? Is the Tightness Right After a Result?

Not really. The tightness you feel right away is mostly the heat talking. With RF treatments done from the skin's surface, a slight tightening is common straight after a session, but your body needs time to build new collagen, and the best results tend to appear at about 6 months*.

*Based on patient guidance from the American Academy of Dermatology (AAD).

Redness and swelling come along with it. In a group of 22 people who had Forma under the chin, almost everyone had temporary redness right after treatment. Photos taken during the few puffy days afterward aren't useful for judging change. If you want the day-by-day recovery picture, we've covered it in InMode FX swelling and bruising.

How Long Until InMode FX Shrinks Double Chin Fat?

Fat under the chin keeps shrinking for months after you finish. In a study of 20 women treated on the belly with an FX-type device, fat volume was down by an average of 202.4 cc one month after the last session. By 3 months, it was down 428.5 cc, and fat thickness had dropped by an average of 39.6%.

Keep in mind those numbers come from the belly, so they don't transfer directly to the area under your chin. What does carry over is the pattern: the change at 3 months was clearly bigger than at 1 month. Individual results vary with how much fat you start with.

If you feel nothing has happened, check the timing first. Before the 1-month mark after your last session, fat change usually hasn't fully shown yet. Then check your weight. In a study of 21 people who had 6 weekly belly sessions, body weight dropped at 1 month but wasn't meaningfully different from the start at 3 months (73.9 kg to 73.3 kg). Writing your weight down alongside your photos makes chin thickness much easier to read.

How Many InMode Forma Sessions Do You Need for Jawline Sagging?

In the main study on this, 22 people with loose skin under the chin had Forma 4 times, 2 weeks apart. Their sagging scores improved meaningfully after the 2nd session, and the doctors' physical assessment improved after the 3rd. Fat volume was also lower than at the start at every check, from 1 week out to 6 months. How much you see depends on your skin.

If your skin is quite loose, InMode alone may fall short of what you're hoping for. Nonsurgical skin tightening tends to suit people with a small amount of sagging, and it can't match surgery. At the visit, the doctor looks at your whole face first, including its balance and any left-right difference, then decides how to weight FX and Forma depending on whether fat or loose skin is the bigger factor.

InMode Side Effects: What's Normal and What Needs a Call?

Redness and swelling are common and tend to be mild and short-lived. A review of 15 facial RF studies found these reactions were mild and temporary, with no serious complications reported. That said, if too much heat stays at the skin's surface, a blistering burn can happen. Contact the clinic right away if you notice:

• Blisters where you were treated

• Redness that doesn't fade after several days

• A dent or sunken spot in the treated area

For a sense of how rare these are, records from 290 people who had 757 treatments with a different, monopolar RF device showed blistering burns in 2.7% of sessions and lasting redness in 1.22%. Fat loss that left a dent was reported even less often. It's a different device, so those numbers don't apply directly to InMode. If a blister forms, never pop it. Keep it covered and get in touch.

It's better to put off treatment if any of these apply:

• You're pregnant

• There's a skin infection in the area to be treated

• You take regular medication (tell the doctor before treatment)

Fitting InMode Into Your Travel Itinerary in Korea

If you're planning InMode during a trip, three things are worth sorting out before you book.

First, flying. Unless you had sedation on the day of treatment, there's no need to postpone treatment because of a flight home.

Second, what one visit can do. Some treatments, like filler, change your shape the same day, but InMode isn't one of them. It works gradually over a series, and the Forma study used 4 sessions 2 weeks apart. Ask ahead how many sessions fit your stay and how the rest would be timed.

Third, after you're home. The bigger fat change tends to happen in the 1 to 3 months after you leave. If something worries you, you can send photos through the consultation button on this page. If a reaction looks serious, such as blisters or spreading redness, see a local doctor first instead of waiting for a reply.

The Bottom Line: When to Take Your Comparison Photos

Take photos before you start, right before each session, and at 1 and 3 months after your last one. Use the same light, the same distance, and both front and side views. Keep your chin level with the floor, because tilting your head up or down changes how a double chin looks.

Before you decide, ask: "For the area under my chin, would you lean on FX or Forma, and how many sessions?" That one answer tells you whether the plan is aimed at fat or at loose skin. Beautystone is a clinic in Seoul's Hapjeong area. When you reach out, include how many sessions you've had, the date of your last one, your comparison photos, and any weight change since then.

Sources

• Forma for loose skin under the chin in 22 people, 4 sessions 2 weeks apart, J Cosmet Dermatol, 2022

• Belly fat volume and thickness at 1 and 3 months in 20 women, J Cosmet Laser Ther, 2016

• Belly fat and body weight after 6 weekly sessions in 21 people, Lasers Surg Med, 2014

• Review of 15 facial RF studies on results, side effects, and pain, Aesthet Surg J Open Forum, 2025

• Burns and lasting redness after 757 monopolar RF treatments, J Cosmet Dermatol, 2007

• When nonsurgical skin tightening results appear and who it suits, American Academy of Dermatology