The calculated distance (air line) between Phasi Charoen and Krathum Baen is approximately 13 miles respectively 20 kilometers.
By car or train, the actual journey to Krathum Baen is certainly longer, as only the direct route (as the crow flies) between Phasi Charoen and Krathum Baen has been calculated here.
Air line (approximately)
20 kilometers
11 nautical miles