The first day sleeping on the mattress it was pretty firm. Now on day 4 it is getting more and more comfortable. Great mattress for the price. I slept on it the first night it arrived and it got up to about 12 inches as soon as I unwrapped it. The biggest complaint I have is the shipping was very inaccurate and it got delayed a week (and not because of weather, just fedex) so I had to sleep on a floor. Was not happy.