Is "somebody else" just as fine as "someone else"?

Question

I was wondering if somebody else and someone else were interchangeable, as the former rolls off the tongue better in the context I want to use it.

Can one say somebody else, or is someone else more of an established saying?

Answer 1

While there is no difference in meaning, there is difference in register:

There is no difference in meaning between someone and somebody, but somebody is more common in spoken English, and someone is more common in written English.
(Collins)

The only difference that most native speakers can agree upon is that someone is more formal than somebody (just as anyone is more formal than anybody, and everyone is more formal than everybody). This means that in a sentence like the one below, used in a legal context, someone is a much more likely choice than somebody.

• The bank requires that the deed be signed by someone authorized by the courts.

It’s also interesting to note that someone is used more frequently than somebody, according to the data that we have on language use.
(Britannica)

This may be the reason why Google Ngram finds someone else much more common (because it searches written texts).

However, if register is not so important for your context, somebody else is perfectly fine. Oscar Wilde uses it:

They are always asking a writer why he does not write like somebody else, or a painter why he does not paint like somebody else, quite oblivious of the fact that if either of them did anything of the kind he would cease to be an artist.
(The Miscellaneous Writings of Oscar Wilde)