What is the length of a double decker bus in feet?

This depends on the type of double decker bus. Here are a few popular urban city models.

~ Lion City Man A95-----------------39.3ft/42ft ~ Lion City Man A39 ----------------45ft ~Enviro500 (SG❤️BUS 3 door bus)*-42.65 ft ~Volvo B5TL-------------------------34.4 ~Volvo B8L**-------------------------39.3 ft ~London New Route Master--------36.8ft ~Enviro 400-------------------------34.1 ft

**4 Prototypes Known( Hong Kong, Singapore..) *Also Known as a Enviro 600.

I hope i answered your question!