How large are the pilot rest areas of the A380 and B747-8?
The pilot crew rest areas are not as large as flight attendant rest areas as they only provide space for 2 occupants. A380 and B747-800 pilot rest areas will have 2 sleeping berths, and most airlines will also have 2 comfortable seats equipped with the same in-flight entertainment as the passengers. This gives the resting pilot the choice to sleep in a bed, or relax in a comfortable chair. Sometimes, instead of a chair in the crew rest area, a regular Business class seat will be blocked for the pilot's use.
Airbus A380
Airbus A380 Pilot Crew Rest Area Video

Boeing 747
The B747-800 Pilot Rest area is behind the flight deck. This photo shows 2 bunks with blue bedding. Crew rest seats may or may not be available depending on the airlines own specifications or requirements.