The iPhone Ultra will be the thinnest iPhone ever — here’s how it will stack up to other foldables

When you’re about to launch your first-ever foldable device, you know it needs to leave a lasting impression. That’s why design is paramount to making the iPhone Ultra compelling — a device already tipped to be the thinnest iPhone ever.

Apple’s entry into the foldable market isn't just another product launch because it’s a defining moment that will set the hardware benchmark for what an ultra-premium, notebook-style foldable should be. While Apple has the chance to set a new standard with its record-breaking thin chassis, it faces fierce competition from rivals like Samsung, Motorola, and Google, who have spent years iterating their designs.

Here’s what the rumors and leaks say about how thin Apple could make the iPhone Ultra.

It’s going to be thinner than the iPhone Air

There’s very little doubt by now that the iPhone Ultra is going to be a solid contender for best foldable phone when it’s released. In fact, one of the biggest reasons for that comes from a longstanding rumor that it will be the thinnest iPhone ever at 4.5 mm unfolded — something reliable leaker Ming-Chi Kuo has claimed for more than a year now.

At under 5 mm, it would easily undercut the ultra-slim iPhone Air’s impressive 5.64mm chassis and blow past traditional slates like the standard iPhone 17. What’s even more impressive is how the Ultra still retains a thin construction when closed, with rumors suggesting it would sit around 9mm to 9.5mm thick — only marginally thicker than the current iPhone 17 Pro and 17 Pro Max.

Comparing the folded and unfolded states to Apple’s current lineup highlights just how dramatic this level of engineering is:

The weight story reveals the inevitable balancing act of having a phone with dual screens. Leaks suggest the iPhone Ultra will tip the scales between 8.1 and 8.5 ounces (230 to 241 grams). While that's substantially heavier than the current iPhone Air and iPhone 17, it puts Apple’s first foldable directly in line with the iPhone 17 Pro Max — giving users a tablet-sized 7.8-inch inner display without adding meaningful heft beyond Apple’s largest flagship.

Impressively thin, but not the thinnest

While the iPhone Ultra’s rumored 4.5 mm unfolded profile would make it a standout within Apple’s lineup, it still wouldn’t be the thinnest notebook-style foldable on the market. Backed by years of iterative engineering, Android rivals have pushed physical dimensions to the absolute limit.

Here in the U.S., Samsung’s Galaxy Z Fold 8 Ultra holds the title with its astounding 4.1 mm profile when unfolded. Seeing is believing, as the ultra-thin chassis leaves you wondering how companies like Samsung manage to cram high-end hardware into such slender frames. However, even Samsung’s latest flagship is a smidge thicker than the reigning global titleholder: the Honor Magic V6, which shaves even more off its waistline with a 4.0mm unfolded build.

In terms of heft, the iPhone Ultra's estimated weight of 230 to 241 grams puts it squarely in the middle of the pack. It won't quite match the featherweight engineering of Samsung's standard Galaxy Z Fold 8 (201 grams) or the Honor Magic V6 (219 grams), but it comfortably undercuts chunkier alternatives like the Motorola Razr Fold (228 grams) and Pixel 11 Pro Fold (245 grams).

For a first-generation foldable, matching the thickness and ergonomics of established devices proves Apple isn't treating the iPhone Ultra as an experiment, but as a refined flagship designed to compete head-to-head on from day one.

But it could come at a cost

Even if the iPhone Ultra doesn’t walk away with the undisputed crown for the world’s thinnest foldable, the engineering behind its design will still be a milestone for Apple. Thinness is only half the battle because if Apple manages to pair its slim chassis with a truly crease-less inner display, MagSafe connectivity, and the strong performance of an A20 Pro chip, it could set a new gold standard for foldables.

The ultimate test, however, will be the price tag. Leaks and rumors hint that the iPhone Ultra price could land anywhere between $2,000 and $2,500, so the iPhone Ultra’s eye-watering cost could easily be a dealbreaker for mainstream buyers. Yet, if Apple somehow delivers on its ambitions, that steep price could establish the Ultra as worth every penny.

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