The calculated distance (air line) between Nieder-Ingelheim and Rüsselsheim is approximately 16 miles respectively 25 kilometers.
By car or train, the actual journey to Rüsselsheim is certainly longer, as only the direct route (as the crow flies) between Nieder-Ingelheim and Rüsselsheim has been calculated here.
Air line (approximately)
25 kilometers
14 nautical miles