I Don't Know If My Hamster Is Dead Or Hibernatin. How Can I Tell?

Well,first check if hes warmer than usually,if he is you might want to take him out of his cage if he doesn't wake up you need to fell his cheeks if they feel like they have anything in them then that means hes storing up for winter but if nothing is there then you might need to push him around a bit if nothing happens then theres one more thing you can do,get food hold it up to his nose his nose should move a little or his whiskers could move or something if nothing happens hes dead.

If it is twitching and its eyes are half open, it may be hibernating. Keep it in a warm room or around a heater, With luck it will soon wake up.

Hamsters DO hibernate its actually a different term this can be come by a few things however, this does depend on the type of hamster you have. I just went through having my hamster passing away, Syrian (teddy bear) hamsters can go into hibernation at which point they take one breath of air every 2 minutes and their heartbeats 4 times a minute.

The thing to check is if your hamster flinches when you touch its whiskers or check its cheeks as they may be a little warmer than the rest of the body. The hamster should also be a limp and not stiff like a board when it is in this state. Best thing to do is check with a vet though.

My hamster is lying on it's back and not moving.  Do hamsters usually lie on their back?

No, they do not lie on their back, and if he's stiff than he has died. When anything alive dies it goes through rigor mortise, that means that the muscles and tendons have hardened up, and fluids have ceased to move. Stiff, cold and smelly means that he's dead.

Hamsters are not true hibernators.  If the ambient temperature is kept appropriately warm enough they will not hibernate.  At low environmental temperature they will become very lethargic and slow their body function.  This can be mistaken for severe illness or death.  
I am concerned about your hamster.  The signs you are describing could be permissive hibernation due to low ambient temperature or could be more serious--the result of an illness.
Warm your hamster's environmental temperature; if the hamster does not start to respond and become more active take this hamster to see a veterinarian.

As long as the temp is above the 60's she will not hibernate. Ideal is around 68-70. She may be dehydrated if she hasn't had water. You can give her childrens unflavored pedialyte to rehydrate if it isn't too late. If she improves add some vitamins to her water. These are at the pet store.

I'm having the same problem this morning - btw 'guest' they do hibernate when the room drops in temp. They become torpid

My hamster is stiff as a board but wen I blow at it it looks like its breathing could any1 help my it it dead or hibernating? I'm 10 so I apologize if it don't make Senice