Often there arises confusion in the minds of the users, between 4K and 1080P, which resolution shall be perfect for the home theater. Here is the difference between the two so that you can buy your best 4K home theater projector with confidence.

4K vs. 1080P

The visuals are comfortable for the eyes.In 4K projectors, you get over eight million pixels which build an immersive experience. It creates UHD picture quality in the home theater.
In 4K projectors, you get more lumens making the projection bright even under ambient light conditions.The number of lumens offered is good but not as high as 4k home theaters.
Great contrast levels and so the images delivered are crisp and clear. There is a clear distinction between black and white levels.The contrast levels are good but lack the quality which is possible by 4K. The black levels appear greyish.
Much lesser input lag.The levels of input lag are higher than 4K home theater.
High refresh rates and so it is perfect for watching hi intensity movies or action movies.The refresh rate is good but not as high as 4k projectors. There shall be a little slowness or blurry scenes during high-impact action scenes. Even it shall be a little challenging for streaming games as most games come in 4K resolution these days.
Upscale image resolution and smooth visuals.Surely there is a difference in the quality of smoothness in the visuals in comparison to 4K projectors.
The visuals are comfortable to the eyes.The visuals are good but there is a difference in the comfort levels from 4K.