It may be subject to financing, inspection etc.
Many attorneys put in a clause that your liability should you break it is limited to your deposit.
If you just entered into an offer some sellers understand buyers getting cold feet and don't hold them to the contract as they realize that the buyer will get out later for inspection issues or financing issues.
I suggest if its an offer you speak with your buyer agent, if it is a purchase and sales, speak with your attorney. These two will be best to advise you.