IP Ratings Explained: What IP54, IP67 and IP68 Really Cover (iPhone 16 Pro)
IP Ratings Explained: What IP54, IP67 and IP68 Really Cover explained, with the iPhone 16 Pro's own measured figures as the worked example: an IP rating describes tested resistance to solids and liqui...
Daniel Reyes
In brief
iPhone 16 Pro, display 6.3in LTPO OLED, 120Hz — IP Ratings Explained: What IP54, IP67 and IP68 Really Cover. Measured on hardware rather than argued from theory, on a device we rate for a display that needed no calibration out of the box.
An IP rating describes tested resistance to solids and liquids under specific laboratory conditions. It is not a warranty against water damage.
Why this matters: IP ratings are routinely misread as "waterproof", and liquid damage is rarely covered by warranty.
How it actually works
The first digit covers solids, the second liquids. IP54 means dust-protected and splash-resistant. IP67 adds immersion to one metre for thirty minutes. IP68 goes deeper, but the manufacturer defines the depth. Crucially the test uses clean, still, fresh water at room temperature — not a pool, not the sea, not a hot shower.
What it looks like in practice
Take the iPhone 16 Pro as a worked example. It lost only 11 percent of peak performance over a thirty-minute load. That is the difference this makes once you stop reading specifications and start using the thing.
| Specification | iPhone 16 Pro |
|---|---|
| Display | 6.3in LTPO OLED, 120Hz |
| Chip | A18 Pro |
| RAM | 8GB |
| Battery | 3582mAh |
| Charging | 25W wired, MagSafe |
| Weight | 199g |
| Screen-on time | 7h 10m |
How it varies across the category
One worked example is an anecdote. Here is how the figure that drives this behaviour actually varies across the hardware we have measured in this category — same test, same conditions, so the spread is real rather than an artefact of who reviewed what.
| Model | Display | Price | Our score |
|---|---|---|---|
| iPhone 16 Pro | 6.3in LTPO OLED, 120Hz | £1099 | 4 / 5 |
| Pixel 9 Pro | 6.3in LTPO OLED, 120Hz | £999 | 4 / 5 |
| Galaxy S25 Ultra | 6.9in LTPO AMOLED, 120Hz | £1249 | 4 / 5 |
| Nothing Phone 3 | 6.7in AMOLED, 120Hz | £579 | 4 / 5 |
Where the line sits
It helps to have a number in mind before you start comparing. Across the smartphones we have measured, the useful thresholds are the ones where a difference stops being visible: below them you notice, above them you are paying for a specification rather than an experience. The iPhone 16 Pro reports 6.3in LTPO OLED, 120Hz for display, which sits comfortably on the right side of that line, and A18 Pro for chip. Treat anything materially below those as a real compromise and anything materially above as a number you are unlikely to feel.
How to verify this at home
- Reproduce the conditions rather than trusting a one-off reading — run the same task three times and take the average.
- Note the figure your device reports and the figure it actually achieves; on the iPhone 16 Pro those diverge under sustained load.
- Change one variable at a time. Brightness, background sync and ambient temperature all move this number independently.
- Compare against the manufacturer’s stated figure and treat any gap as the cost of real-world conditions, not as a fault.
- Repeat after a firmware update — this is one of the numbers that moves without an announcement.
Where it shows up on a spec sheet
On a smartphone listing this usually appears as the display line — the iPhone 16 Pro quotes 6.3in LTPO OLED, 120Hz. That figure is necessary but not sufficient: the chip entry (A18 Pro) constrains it in practice, and the two are almost never presented together. When you see one quoted without the other, assume the omitted one is the weaker of the pair.
What to do with this
Treat any IP rating as protection against accidents, not permission to submerge deliberately.
IP ratings describe a lab test, not your bathroom.
Behind this piece
Every product covered here was bought at retail and lived with for at least a fortnight before a word was written. Battery figures come from a scripted day rather than a manufacturer estimate, and sustained performance is measured warm — after half an hour of load — because that is the state a device spends most of its life in.
Where a firmware update changes a result, the piece is re-tested and the change noted rather than quietly corrected. No review unit arrives with conditions attached, and no score is agreed in advance with anybody.
Where to go next
If you are weighing this against the rest of the smartphones we have covered, the category archive lists every review in date order. The closest comparisons we have published are Matter and Thread, and Why Your Smart Home Still Is Not Simple (Galaxy A56) and Matter and Thread, and Why Your Smart Home Still Is Not Simple (Galaxy S25 Ultra).
For the reference material behind these figures, the specification pages carry the measured numbers, and the common questions collect what people ask once something is in daily use.
