It is not possible to give an exact answer to this question as President Donald Trump has not released any public information about his waist size. Moreover, different sources will cite varying estimations of his waist size.
However, based on various visual estimates, it can be estimated that President Donald Trump's waist size is somewhere between 39 and 40 inches, as reported by both The Huffington Post (source: https://www.msn.com/en-gb/news/other/what-is-donald-trumps-waist-size/ar-AAhq3Gw) and Business Insider (source: https://www.businessinsider.com/donald-trumps-size-clothing-waist-hands-2019-11).
Nevertheless, it is important to note that without an official measurement from the president, these estimations must remain unconfirmed.
