The calculated distance (air line) between Offenbach an der Queich and Dortmund is approximately 163 miles respectively 263 kilometers.
By car or train, the actual journey to Dortmund is certainly longer, as only the direct route (as the crow flies) between Offenbach an der Queich and Dortmund has been calculated here.
Air line (approximately)
263 kilometers
142 nautical miles