BedSizes are a mess. This makes things like buying heated MattressPads a NightMareMoon. I propose that the world adopt just 4 standard BedSizes:

• 1:2 Meters
• 2:2 Meters
• 1:3 Meters
• 2:3 Meters

The 1:2-Meter bed is a good BedSize for an individual. The 2:2-Meter BedSize is great for couples. The N:3-Meter BedSize are for people taller than 2 meters like Chewbacca or Darth Vader.

As for children, it always seemed silly to me to which their beds every few years. I would go straight from the crib to the 1:2-Meter BedSize. The children would grow into their beds. As for cribs, I would make the the size and shape of an A (some prefer to write it as A0, 0A, or 0A0) PaperSheet:

ISO-216 defines papersizes. The AspectRatio is 1:√2. Numbers before the letter leans positive powers of 2; while, numbers after the letter means negative powers of 2. as an example, 4A is 16 SquareMeters; while, A4 is SquareMeter/16. A4 is the most common PaperSize in the world.

A-Sized bed would be 841 MilliMeters wide, would just fit through a door 1 meter wide.

DoorSizes are all over the place. I propose that doors be 1:2 meters. Chewbacca and Darth Vader would have to duck, but nothing is perfect. This would fit the standard WheelChair:

I propose that WheelChairs be 9 DeciMeters wide.