401K fee, hhtt?

I was always told that mutual funds in the 401K charged less fee than the regular.   Do you know how much higher is the fee of 401K in general?  How can we tell? Thanks.  

"The first big benefit by rolling over to an IRA is that you have just lowered your management fees significantly since 401(k) or 403(b) administrators charge a higher fee than most of mutual fund companies.  These fees are all hidden from you and it is hard to find on your 401(k) or 403(b) statements."