Mr. Peanut's Gold Series Standard (Expandable) vs Sherpa Original Deluxe (Medium): which airline pet carrier?
Two of the most cross-shopped in-cabin carriers, compared the way an airline sees them: by published size against each under-seat limit. Mr. Peanut's Gold Series Standard (Expandable) is 18.5 × 11.75 × 11.5 in; Sherpa Original Deluxe (Medium) is 17 × 11 × 10.5 in.
Side by side
| Property | Mr. Peanut's Gold Series Standard (Expandable) | Sherpa Original Deluxe (Medium) |
|---|---|---|
| External size (L×W×H) | 18.5 × 11.75 × 11.5 in | 17 × 11 × 10.5 in |
| Type | soft-sided · flexible height · expandable | soft-sided · flexible height |
| Pet weight | — | up to ~16 lb |
| Airlines it fits outright | 0 of 58 | 7 of 58 |
Airline by airline
Green = within the published size; amber = fits only collapsed / flexed; grey = over. Height is strict — it's the dimension a seat won't negotiate on.
| Airline | Gold Series Standard (Expandable) | Original Deluxe (Medium) |
|---|---|---|
| Aegean Airlines | Too big | Too big |
| Air Canada | Too big | Flexes — check height |
| Air France | Too big | Flexes — check height |
| Air New Zealand | No cabin pets | No cabin pets |
| Air Transat | Too big | Too big |
| Alaska Airlines | Too big | Flexes — check height |
| Alaska Horizon (Horizon Air) | Size not published | Size not published |
| Allegiant Air | Too big | Fits |
| American Airlines | Too big | Fits |
| American Eagle (regional, incl. Republic Airways) | Too big | Too big |
| ANA (All Nippon Airways) | No cabin pets | No cabin pets |
| Austrian Airlines | Flexes — check height | Flexes — check height |
| Avelo Airlines | Too big | Too big |
| Avianca | Flexes — check height | Flexes — check height |
| Azul Linhas Aéreas | Size not published | Size not published |
| Breeze Airways | Too big | Too big |
| British Airways | No cabin pets | No cabin pets |
| Brussels Airlines | Flexes — check height | Flexes — check height |
| Cape Air | Too big | Flexes — check height |
| Cathay Pacific | No cabin pets | No cabin pets |
| China Airlines | No cabin pets | No cabin pets |
| Contour Airlines | Flexes — check height | Flexes — check height |
| Delta Air Lines | Too big | Fits |
| easyJet | No cabin pets | No cabin pets |
| EL AL Israel Airlines | Too big | Too big |
| Emirates | No cabin pets | No cabin pets |
| Etihad Airways | Too big | Too big |
| Finnair | Too big | Too big |
| Frontier Airlines | Too big | Fits |
| GOL Linhas Aéreas | Too big | Too big |
| Hawaiian Airlines | Too big | Flexes — check height |
| Iberia | Too big | Flexes — check height |
| ITA Airways | Flexes — check height | Flexes — check height |
| Japan Airlines | No cabin pets | No cabin pets |
| JetBlue | Too big | Flexes — check height |
| JSX | Too big | Fits |
| KLM Royal Dutch Airlines | Too big | Flexes — check height |
| Korean Air | Too big | Flexes — check height |
| Lufthansa | Flexes — check height | Flexes — check height |
| Norwegian | Too big | Too big |
| Porter Airlines | Flexes — check height | Fits |
| Qantas | No cabin pets | No cabin pets |
| Qatar Airways | No cabin pets | No cabin pets |
| Royal Air Maroc | Flexes — check height | Flexes — check height |
| Ryanair | No cabin pets | No cabin pets |
| SAS Scandinavian Airlines | Too big | Too big |
| Singapore Airlines | No cabin pets | No cabin pets |
| Southern Airways Express | Size not published | Size not published |
| Southwest Airlines | Flexes — check height | Flexes — check height |
| Sun Country Airlines | Too big | Flexes — check height |
| Swiss International Air Lines | Flexes — check height | Flexes — check height |
| TAP Air Portugal | Too big | Flexes — check height |
| Turkish Airlines | Too big | Too big |
| United Airlines | Too big | Fits |
| Virgin Atlantic | No cabin pets | No cabin pets |
| Volaris | Too big | Flexes — check height |
| Vueling | Too big | Flexes — check height |
| WestJet | Too big | Too big |
Choose the Mr. Peanut's Gold Series Standard (Expandable) if…
- Flex height plus side expansion. At 18.5" long / 11.5" tall it's a big-carrier — best on the 11" airlines.
- It clears 0 of 58 tracked airlines outright.
Choose the Sherpa Original Deluxe (Medium) if…
- Spring-wire top flexes down to squeeze under lower seats. Guaranteed On Board®.
- It clears 7 of 58 tracked airlines outright — more than the Mr. Peanut's Gold Series Standard (Expandable).
- Your pet is under ~16 lb.
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Full profiles: Mr. Peanut's Gold Series Standard (Expandable) · Sherpa Original Deluxe (Medium) · best carriers ranked · all carriers
Common questions
Which fits more airlines, the Mr. Peanut's Gold Series Standard (Expandable) or the Sherpa Original Deluxe (Medium)?
The Sherpa Original Deluxe (Medium) — it's within the published limit of 7 of the 58 airlines we track, against 0 for the other. Real under-seat space still varies by aircraft.
What's the size difference?
Mr. Peanut's Gold Series Standard (Expandable): 18.5 × 11.75 × 11.5 in. Sherpa Original Deluxe (Medium): 17 × 11 × 10.5 in (up to ~16 lb). Height is the strict dimension under a seat, and the Sherpa Original Deluxe (Medium) is the shorter of the two.
Are these figures measured or published?
Published — both sets of dimensions come from the manufacturers' product pages (linked on each carrier's profile), matched against each airline's official carrier limit. We don't invent measurements.