The calculated distance (air line) between Nykøbing Sjælland and Næstved is approximately 48 miles respectively 77 kilometers.
By car or train, the actual journey to Næstved is certainly longer, as only the direct route (as the crow flies) between Nykøbing Sjælland and Næstved has been calculated here.
Air line (approximately)
77 kilometers
42 nautical miles