According to Young, the iPhone 12 lineup is expected to consist of the base iPhone 12, the iPhone 12 Max, the iPhone 12 Pro, and the iPhone 12 Pro Max. The base model will sport a 5.4-inch display with a resolution of 2340×1080. As for the Max version, it will sport a slightly larger 6.1-inch display with a higher 2532×1170 resolution.
Next up will be the Pro models, where the iPhone 12 Pro will share the same 6.1-inch display and 2532×1170 resolution as the iPhone 12 Max, while the top-of-the-line model, the iPhone 12 Pro Max, will come with a whopping 6.7-inch screen and the highest resolution of 2778×1284. Apple typically does not display resolution and usually prefers to just refer to it as a Retina Display (which needs to have a minimum pixel density to be considered Retina).
That being said, since none of this can be confirmed yet, you should probably take it with a grain of salt for now, and hopefully there are no delays in the iPhone 12’s launch and that we should have more details towards the later part of the year.