Standard door width for bedrooms, baths is 32". Closets anywhere from 24" to 30". If you think you may need to move large furniture in/out, or someone in a wheelchair, go with 36" but that's usually just for exterior doors.

30" or 32" for all houses we've lived in for bedrooms and bathrooms. Our code stipulated at least one bathroom door needs to be 32".

There has been at least one recent thread on this topic, with lots of opinions and experiences. You may want to search for it.

If yours is a custom house, to be built, I'd make all doors where major circulation occurs (and where large furniture and other objects may be moved in/out) 36" wide. Any doors necessary for wheelchair or universal design would also be best at 36", IMO.

Tract and builder homes tend to commonly use narrower doors, but if you are building and planning to live in your house for an extended period, the wider doors will prove beneficial.

Good luck on your project.

(personally, I find 34" to be a very comfortable width--not too narrow for laundry baskets, but not too wide for door swing floor space issues)

We went with 36" doors on our first floor, and I love them. It is so much easier to move furniture around. They looked "big" to me at first, but now they just look normal.....and the more "normal" sized doors on the 2nd floor now look tiny.

We had a 24" bathroom door in a previous home it always felt tiny. The smallest door we put in our new home was 2'4 (28").