This is a problem that I’m scared of when I’m going to do a game. I don’t know what is the perfect size of images to have a good quality in every device, including XBOX and more.
I want to stop being scared at this problem having a solution to it, I would be very pleased if you could tell me what is the perfect size to have a good quality image and what recommendations you give me when I’m going to do images for my game.
Please.
The ratios for icons are 1x1 and for thumbnails is 16x9. Maximum size is 512x512 for icons and 1920x1080 for thumbnails and other decals. Anything larger will be compressed, and anything smaller will be more blurry. This way the images looks nice over every platform.
Hope i have helped 
So like, for example if I want to make a square of wood, do I have to use 16x9 or 512x512?
It would depend upon how big and clear ur square would be, but i feel a 512x512 would be perfect
Okay! I will try doing it then, thank you so much!
Hey I need a little help too, please! You said that 1920x1080 was the max size for decals, and I tried to use an image of 1024x361, and found out that it got downscaled to 420x420. I tried 512x181, and it got downscaled to 420x420 again. Do you have any idea how this can be fixed.
EDIT: I Downscaled it manually to 420x136 and it works! It’s some pixels lost, but works
Glad it worked for you too, I find myself in such problems every now and then and figured it out through trial and error