Best airlines in all classes: Qantas named among best airlines in all classes in airline ratings

Qantas and Singapore Airlines have been ranked among the best in the world across four separate cabin classes by AirlineRatings.com.

The website, which ranks airlines alphabetically on their safety, comfort and luxury, has named the best in long-haul economy, first class, business class and premium economy, with carriers from Oceania, the Middle East and Asia dominating.

The ranking named Emirates, Etihad, Japan Airlines, Korean Air, Lufthansa, Qantas, Singapore Airlines, Swiss and Thai Airways as the 10 best for first class cabins.

For business class cabins, Air France, Air New Zealand, All Nippon Airways, Cathay Pacific, Etihad, Japan Airlines, Qatar, Qantas, Singapore Airlines and Virgin Australia/Atlantic topped the list.

Best in premium economy class cabins included Air France, Air New Zealand, British Airways (the airline's only appearance on the rankings), Cathay Pacific, Japan Airlines, Qantas, Singapore Airlines and Virgin Atlantic/Virgin Australia.

For long haul economy class cabins, the top 10 airlines included: Air New Zealand, Cathay Pacific and Etihad, all three airlines making their third appearance in the rankings; Japan Airlines; Korean Air, which makes its only appearance on the rankings; Qantas; Qatar; Singapore Airlines and Thai Airways.

Qantas and Singapore were the only two airlines which scored among the top 10 best for its first, business, premium economy and long-haul economy classes in the rankings.

AirlineRankings.com deems first class to be the "ultimate in luxury and space."

"First class is essentially the same philosophy as business class but with more space, privacy, meal courses, the finest of champagnes, wine and liquors and you rarely have to see another passenger," the website reported.