Toilets, Sinks, Showers, Tubs and Disposals - 3" or 4" flange and closet bend?

New here. New toilet install.

I bought a 3" flange which seems like it will accept a 3" pipe (into it). Do I need a special "closet bend"? Should the flange insert INTO the next piece or should a length of 3" pipe go inbetween to the next joint/coupling.

Now looking at my 'helpful' book, it says to have a 4" flange with a 4" to 3" reducing closet bend! Would a 4" flange be too big for a standard toilet? 3"? 4"? Help.

I can't find a clear schematic anywhere of exactly how to piece these parts.

If using a 3" flange, you need either a piece of pipe between the flange and 3" closet bend or a 3" "street" closet bend. A street fitting has a female "cup" on one end to accept a pipe inside it and a male fitting on the other end that your flange would go onto. Good luck.

Thanks for you response. But now I'm confused. There is a "male" fitting that something goes into?

I ran to HD and picked up a closed bend...

Now I have a 3" flange that fits into the completely smooth side of this closed bend (there is not coupling on that end), and the other end of the closet bend has a coupling (female) that accepts a 3" pipe.

Is this right?

At HD, I played with the parts and saw that a 4" pipe received the 3" closet flange, but I couldn't find the right closet bend that would accept that 4" pipe and downsize to a female coupling for a 3" pipe.

#2. Why would one choose a 3" vs. a 4" flange?

Okay, you are using a flange that goes INSIDE the fitting. The street elbow I was talking about, the flange would go ONTO the end and be glued there. The flange would be the female fitting going on to a male pipe end. The reason most people go 3" flanges is due to the fact that most houses have 3" main waste lines or 3" toilet drain piping. No reason to change pipe size for a flange. Largest toilet exit hole I have seen is 2-3/8" so anything over 3" is overkill. (unless your main and toilet drainpipe is 4".)