Apple publishes the same three measurements for the iPhone 18 Pro as it did for last year’s iPhone 17 Pro: 150.0 mm tall, 71.9 mm wide and 8.75 mm deep. The two Pro Max models match each other the same way, at 163.4 x 78.0 x 8.75 mm.
The only published dimension that moved is weight. The iPhone 18 Pro is 211 g against 206 g, and the 18 Pro Max is 249 g against 233 g. Apple has explained neither increase.
Key facts: four Pro models, two footprints
| Model | Height | Width | Depth | Weight |
|---|---|---|---|---|
| iPhone 18 Pro | 150.0 mm | 71.9 mm | 8.75 mm | 211 g (7.44 oz) |
| iPhone 17 Pro | 150.0 mm | 71.9 mm | 8.75 mm | 206 g (7.27 oz) |
| iPhone 18 Pro Max | 163.4 mm | 78.0 mm | 8.75 mm | 249 g (8.78 oz) |
| iPhone 17 Pro Max | 163.4 mm | 78.0 mm | 8.75 mm | 233 g (8.22 oz) |
Apple’s iPhone 18 Pro tech specs page gives the same body in inches, at 5.91 x 2.83 x 0.34 for the Pro and 6.43 x 3.07 x 0.34 for the Pro Max, while the comparison page carries the millimetre figures. Both sets round to the same phone.
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Five grams on one model, 16 on the other
The weight increases are not proportional. The 6.3-inch Pro gained 5 g, a rise of about 2 percent, and the 6.9-inch Pro Max gained 16 g, closer to 7 percent, inside bodies of exactly the same published size.
One consequence is that the gap between the two sizes widened. Last year 27 g separated the 17 Pro and 17 Pro Max. This year 38 g separates the Pro and the Pro Max, which is the single largest difference in the choice between the two sizes.
Apple publishes no battery capacity, no memory figure and no component weights for any iPhone, so there is no published account of where the extra grams went.
The depth figure travels furthest of the three. At 8.75 mm it now covers four phones across two generations, since both 2026 Pro models share it with both 2025 Pro models. Apple describes the 2026 body as an aluminum unibody with a Ceramic Shield 2 front and a Ceramic Shield back, with 40 percent recycled content overall.
What changed inside the same shell
| Specification | iPhone 17 Pro | iPhone 18 Pro |
|---|---|---|
| Chip | A19 Pro | A20 Pro, Apple’s first 2-nanometer iPhone chip |
| Main camera | 48MP Fusion, 24 mm, f/1.78 | 48MP Fusion, 24 mm, variable aperture f/1.48 to f/4.0 |
| Video playback rating | Up to 33 hours | Up to 36 hours |
| Wired fast charge | 50 percent in 20 minutes, 40W | 50 percent in about 15 minutes, 60W |
| Storage ceiling | 1TB | 2TB |
| US launch price, 256GB | $1,099 | $1,199 |
The generational story is therefore internal rather than external. The differences between the 18 Pro and 17 Pro sit in the chip, the camera system, the charging claim and the storage ceiling, and the variable aperture is the headline among them.
What the sameness changes for buyers
Nothing about handling. A 17 Pro owner moving to the iPhone 18 Pro gets a phone that occupies the same space in a pocket and a hand, with a slightly higher weight and a different finish. The colors changed to Black, Silver, Glacier and Burgundy, and last year’s Cosmic Orange is gone.
Apple has published no statement about whether accessories carry across the two generations, so the matching dimensions are a measurement rather than a compatibility promise. Price did move, by $100 at every tier.
What Apple has not said
Apple has not explained the weight increase, has not published battery capacities or memory for either generation, and has not commented on carrying the same dimensions for a second year. It has also published no case or accessory compatibility statement between the two Pro generations.
Pre-orders open on Saturday, September 12 at 5 a.m. Pacific, with the iPhone 18 Pro and 18 Pro Max in stores on Friday, September 18 in more than 65 countries and regions.