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 × 11 × 10 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 × 11 × 10 in | 17 × 11 × 10.5 in |
| Type | soft-sided · flexible height · expandable | soft-sided · flexible height |
| Pet weight | up to ~20 lb | up to ~16 lb |
| Airlines it fits outright | 8 of 43 | 7 of 43 |
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 — 2.5" over |
| Air France | Flexes — 0.6" over | Flexes — 1.1" over |
| Air New Zealand | No cabin pets | No cabin pets |
| Air Transat | Too big | Too big |
| Alaska Airlines | Too big | Flexes — 1" over |
| Alaska Horizon (Horizon Air) | Too big | Flexes — 1" over |
| Allegiant Air | Exact fit | Fits |
| American Airlines | Exact fit | Exact fit |
| American Eagle (regional, incl. Republic Airways) | Too big | Too big |
| ANA (All Nippon Airways) | No cabin pets | No cabin pets |
| Austrian Airlines | Flexes — 0.9" over | Flexes — 1.4" over |
| Avelo Airlines | Too big | Too big |
| Avianca | Exact fit | Flexes — 0.5" over |
| 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 — 0.9" over | Flexes — 1.4" over |
| Cape Air | Too big | Flexes — 2" over |
| Cathay Pacific | No cabin pets | No cabin pets |
| China Airlines | No cabin pets | No cabin pets |
| Contour Airlines | Exact fit | Flexes — 0.5" over |
| Delta Air Lines | Exact fit | Exact fit |
| 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 | Exact fit | Fits |
| GOL Linhas Aéreas | Too big | Too big |
| Hawaiian Airlines | Too big | Flexes — 1" over |
| Iberia | Too big | Flexes — 0.7" over |
| ITA Airways | Flexes — 0.9" over | Flexes — 1.4" over |
| Japan Airlines | No cabin pets | No cabin pets |
| JetBlue | Too big | Flexes — 2" over |
| JSX | Too big | Exact fit |
| KLM Royal Dutch Airlines | Flexes — 0.6" over | Flexes — 1.1" over |
| Korean Air | Too big | Flexes — 3" over |
| Lufthansa | Flexes — 0.9" over | Flexes — 1.4" over |
| Norwegian | Too big | Too big |
| Porter Airlines | Fits | Exact fit |
| Qantas | No cabin pets | No cabin pets |
| Qatar Airways | No cabin pets | No cabin pets |
| Royal Air Maroc | Flexes — 2.1" over | Flexes — 2.6" over |
| 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 — 1.5" over | Flexes — 2" over |
| Sun Country Airlines | Too big | Flexes — 1.5" over |
| Swiss International Air Lines | Flexes — 0.9" over | Flexes — 1.4" over |
| TAP Air Portugal | Too big | Flexes — 1.5" over |
| Turkish Airlines | Too big | Too big |
| United Airlines | Exact fit | Exact fit |
| Virgin Atlantic | No cabin pets | No cabin pets |
| Volaris | Too big | Flexes — 3" over |
| Vueling | Too big | Flexes — 2.2" over |
| WestJet | Too big | Too big |
Which should you buy?
The Mr. Peanut's Gold Series Standard (Expandable) — it is within the published limit of 8 of the 43 airlines with a published cabin limit, against 7 for the Sherpa Original Deluxe (Medium). That is the whole verdict on airline fit; real under-seat space still varies by aircraft and seat.
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Choose the Mr. Peanut's Gold Series Standard (Expandable) if…
- Flex height plus side expansion: 10" closed, opening to 12". At 18" long it is a big-carrier — best on the 11" airlines.
- It clears 8 of 43 airlines with a published cabin limit outright — more than the Sherpa Original Deluxe (Medium).
- Your pet is under ~20 lb.
Choose the Sherpa Original Deluxe (Medium) if…
- Spring-wire top flexes down to squeeze under lower seats. Guaranteed On Board®.
- It clears 7 of 43 airlines with a published cabin limit outright.
- Your pet is under ~16 lb.
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 Mr. Peanut's Gold Series Standard (Expandable) — it's within the published limit of 8 of the 43 airlines with a published cabin limit, against 7 for the other. Real under-seat space still varies by aircraft.
What's the size difference?
Mr. Peanut's Gold Series Standard (Expandable): 18 × 11 × 10 in (up to ~20 lb). Sherpa Original Deluxe (Medium): 17 × 11 × 10.5 in (up to ~16 lb). Height is the strict dimension under a seat, and the Mr. Peanut's Gold Series Standard (Expandable) 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.