This used to be a competition among friends when I was a lifeguard, most people could only go for 1-2 minutes before coming up. A few rare individuals could go several minutes, but it took a lot of relaxation and hyperventilation before hand to achieve. I think most extreme skin divers can hold their breath around 5-6 minutes.
BTW, pinching your nose Makes a difference. Rather than letting air passively flow to your lungs, that is something I have noticed anyway. But I can hold my breath for about 40 seconds underwater.