Ending a sentence with a preposition is grammatically valid and often more natural

Evidence

The name’s origin may be largely to blame for the superstition that a preposition should not end a sentence (that is, because it must come before its object). In fact, though, not only can a preposition end a clause (especially a relative clause) or a sentence, but the result often sounds far more natural than the convoluted syntax that the superstition would demand. — Bryan A. Garner, Jeff Newman, Tiger Jackson, The Redbook, 296

Categorization

• XREF: Connects to broader writing-style debates and Garner’s pushback against inherited grammar superstitions across his other usage works.