The calculated distance (air line) between Seeheim-Jugenheim and Duisburg is approximately 142 miles respectively 228 kilometers.
By car or train, the actual journey to Duisburg is certainly longer, as only the direct route (as the crow flies) between Seeheim-Jugenheim and Duisburg has been calculated here.
Air line (approximately)
228 kilometers
123 nautical miles