The Philosophical Gourmet ranks ND #17 (tied with Texas & Cornell).
The NRC’s 10 ranking formulas place ND between #2 and #83.
QS World ranks it 13th (behind NYU, Pittsburgh, Rutgers, Oxford, Harvard, Cambridge, Princeton, LSE, Berkeley).
These are graduate program rankings, which are not necessarily the last word even for graduate/faculty rankings (let alone for undergraduate programs). Graduate program rankings tend to emphasize faculty publication/citation volumes, which may not be too relevant to most undergraduates (although they probably do tell us something about the quality of faculty scholarship.)