To write this guide to the best mattress toppers ... Below, we’ve listed the thickness of each mattress topper, and the density when available, as not all brands provide that detail.

All you need to know is that higher-density foam feels firm and solid (the sort of thing you find in a mattress base layer), ...

If it does, you’ll want to buy a new one. Foam mattresses are usually made from high-density polyurethane foam. At about 8 to 13 pounds, foam mattresses tend to be lighter than innerspring ...