The calculated distance (air line) between Phra Pradaeng and Krathum Baen is approximately 18 miles respectively 30 kilometers.
By car or train, the actual journey to Krathum Baen is certainly longer, as only the direct route (as the crow flies) between Phra Pradaeng and Krathum Baen has been calculated here.
Air line (approximately)
30 kilometers
16 nautical miles