About 50% firmer than I thought. It is very sturdy with only a small layer of gel/form which I like so you don't feel the springs exactly. It has very strong edge support as well! I realized even though I'm 175 lbs, this is a little bit too firm for me so next time I'll buy one that is maybe a medium firm rather than firm. If you're over 175 lbs than this is the bed to buy for sure! The quality of the materials is very nice and this has increased my perception of the reputation Serta holds. High quality materials with a high quality brand name. Can't go wrong!