How do you clean a mirror that looks like it is fogged over?

Sounds like the back of the mirror is messed up you would have to put a new silver back on

I use alcohol to clean all glass

Hello there, - Is this an old mirror - sign of age! Antique glass is much desired by some!!

New but has been for a long while in a damp place or been left or kept outdoors?

In any case it is not possible to bring back a mirror that has fogged up due to damp.

But if you feel you want to try - spray canned aerosol mirror much for a perfect job.spay over either front or back, but I don't hold out.

Is it a film, or is it going blind? I have some ancient mirrors too and one is going blind just from age.

Straight vinegar and newspaper

Straight rubbing alcohol & clean wash cloth(no fabric softener on it)

Try vinegar and a rag.

Mix one-part vinegar with four parts water and pour it into the spray bottle. Spray the solution onto the cotton cloth or directly onto the mirror. Before the spray dries, wipe the mirror from side to side or up and down with the cotton cloth. Never wipe the mirror in circles.