A new dummy model has emerged offering a clear view of just how aggressively thin Samsung’s shelved Galaxy S26 Edge might have been, and the figures are eye-catching. The prototype is just 5.5mm thick — that’s thinner than the slim Galaxy S25 Edge and even thinner than Apple’s rumored ultra-thin “Air” variant.
Leak Suggests Radical Slimming for Galaxy S26 Edge
The image posted by trusted tipster OnLeaks on X shows a real-world S26 Edge dummy being measured in calipers and stood alongside an iPhone 16 Pro for scale. The readout is 5.5mm, 0.3mm slimmer than the Galaxy S25 Edge’s 5.8mm. It’s also slimmer than the similarly imagined iPhone 17 Air concept at just 5.6mm, proving exactly how close Samsung took us to the edge before its development was said to be stopped.
Context is important here: Samsung pursued the ultra-thin concept when it created the Edge to build itself a showboat of minimalism, only to scrap its follow-up — according to industry rumor — when demand for that first-gen model was underwhelming compared with the significant and ever-creakier compromises necessary for shaving those last tenths of a millimeter off your phone. The mock-up also appears to confirm Samsung had reached late-stage prototyping before it pulled back.
How 5.5mm Compares with Today’s Flagships
Most premium phones are between about 7.8mm and 9mm. For comparison, the iPhone 16 Pro is roughly 8.3mm thick, and Samsung’s own Galaxy S24 Ultra comes in at about 8.6mm. Pretty slim. At 5.5mm, the S26 Edge dummy is roughly 33% thinner than a typical 8.3mm-class handset and about 3mm more slender in absolute terms — it makes a huge difference to how the phone feels both in your hand and your pocket.
Getting that thin is really more than an aesthetic decision; it’s a remaking of the internal architecture. Even minor reductions necessitate changes to the battery pack, cooling stack, camera assembly, and frame stiffness. So they do their utmost to occupy every last cubic millimeter; hence ultra-thin phones’ reliance on aggressive component miniaturization and exotic layouts.
The Unseen Trade-Offs of Extra-Thin Phones
First to go is the battery capacity. Flagship devices with current lithium-polymer cells are in the roughly 600–700 Wh/L class. Reduce the chassis height and there’s just less volume for cells, while thermal headroom goes up in smoke. Teardown experts like iFixit have long pointed out that ultra-thin designs don’t allow for heat spreaders, vapor chambers, or graphite layers to keep the chipset cool under load for extended periods.
Cameras pose another challenge. Those big sensors and bright optics require z-height. Manufacturers can skimp on the body only to make a thicker camera bump, or shrink the sensors and lenses. The thinnest products frequently make cuts to the sensor size or look instead to more computational photography to fix that — a plan that works up until physics starts interfering with low-light and dynamic range performance.
It is also increasingly difficult to balance structural integrity with radio performance. Ultra-slim frames require stiffer materials and more-complex internal ribs to resist torsion, which can encroach on the antennas. The radio engineers have to dance between rigidity, battery location, and multiband antenna tuning, especially for sub-6GHz and mmWave designs.
Why Ultra-Thin Phone Designs Remain a Niche Choice
Consumers still don’t seem to want razor-thin designs. Industry analysts such as Counterpoint Research and IDC consistently cite battery life, camera performance, and overall performance as the prime drivers in flagship segments. Thin might make for luxury in feel, but it doesn’t typically overrule longevity or pictures in buyer surveys.
That reality has affected how vendors have planned their strategy. Various brands have dabbled with ultra-slim halo devices over the years, only to find that there is a finite audience once the trade-offs become evident: smaller batteries, hotter chips under load, and camera compromises. And the S26 Edge dummy indicates that Samsung might have considered a best-case iteration — but the market signal wasn’t strong enough to justify volume production.
What This Means for Future Samsung Phones
The engineering of the S26 Edge won’t go to waste, even if it never ships. There are hopes that the learnings from this experiment will trickle into future models: thinner vapor chambers, denser cell packaging, more compact periscope assemblies, and lighter-but-better frame alloys. This is the sort of minute-by-minute progress that comes together to make mainstream devices feel thinner without sacrificing battery life.
The leaked dummy is ultimately proof of the possible. The S26 Edge at 5.5mm thick would have been a conversation starter and packaging marvel in its own right. But at least for now — until another jump in energy density, a barrage of thermal solutions, and camera modules somehow break through — ultra-thin has got to be more of a show-off design than the necessarily representative future flagship formula.