Spare tire

Hello everyone, I have a question about the spare tire. It may sound dumb but here goes lol.
I just bought a ‘21 Off Road. Switched the wheels to methods 17 inches with 265/70/17 bfg ko2s. However i have yet to change my spare tire. Would it be possible to keep the 16 inch spare but replace the tire to something close to size as my main ones or would i need the exact same wheel and tire size?
I do not plan on doing any extreme off roading. Was just thinking of having a small spare thats enough to take me to a tire shop.

 

You can keep and use the mismatched spare. However, stay out of 4WD when the spare is employed.

 

oh ok, so the one that i have now 265/70/16 will do fine as a spare then and Shouldnt cause some crazy uneven shakes when i do drive on it?

 

You won't even know it's there.

 

I thought all have to be the same?

 

At the minimum wouldn't the two rear drive wheels have to have the same profile?
i.e. if a rear tire is blown then you would have to take a front to replace the rear then put the spare in the front location and stay in 2WD.

 

No.

 

265/75r16 is the equivalent size to 265/70r17