The first step in your hunt for a high-quality memory foam mattress is picking the right size of mattress. Memory foam mattresses come in all sizes and thicknesses. The term ‘mattress size’ is generally used to categorize mattresses as king size, queen size, twin size etc. This memory foam mattress classification is based on the length and width of the mattress. If you want to discuss about 10 inch vs 14 inch memory foam mattresses, the right term to use is ‘mattress thickness’.

Below we have indicated the dimensions for 13 different mattress sizes. Most of them are standard sizes that you can find at any mattress store. However, we also included a few non-standard sizes like Three-Quarter, Olympic Queen and Super King just to make the mattress size chart as comprehensive as possible.

Here is a simple memory foam mattress size chart

Mattress SizeWidth (inches)Length (inches)Width X Length (cm)
Twin (aka Single)387597 cm × 191 cm
Twin XL388097 cm × 203 cm
Three-quarter4875122 cm × 191 cm
Full (aka Double)5475137 cm × 191 cm
Full XL5480137 cm × 203 cm
Queen6080152 cm × 203 cm
Olympic Queen6680168 cm × 203 cm
King7680193 cm × 203 cm
California King7284183 cm × 213 cm
Super/Grand/Athletic/Texas King8098203 cm × 249 cm
Split Queen308076 cm × 203 cm
Split King388097 cm × 203 cm
Split California King368492 cm × 213 cm

Here are the major mattress sizes illustrated for even better understanding…

Memory Foam Mattress Size Chart