The calculated distance (air line) between Zürich (Kreis 11) / Seebach and Thun is approximately 64 miles respectively 102 kilometers.
By car or train, the actual journey to Thun is certainly longer, as only the direct route (as the crow flies) between Zürich (Kreis 11) / Seebach and Thun has been calculated here.
Air line (approximately)
102 kilometers
55 nautical miles