Diggs Passenger vs SturdiBag Pro (Large, Flexible Height): 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. Diggs Passenger is 17 × 12 × 10.5 in; SturdiBag Pro (Large, Flexible Height) is 18 × 11.5 × 11.5 in.
Side by side
| Property | Diggs Passenger | SturdiBag Pro (Large, Flexible Height) |
|---|---|---|
| External size (L×W×H) | 17 × 12 × 10.5 in | 18 × 11.5 × 11.5 in |
| Type | soft-sided | soft-sided · flexible height |
| Pet weight | — | — |
| Airlines it fits outright | 4 of 43 | 0 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 | Passenger | Pro (Large, Flexible Height) |
|---|---|---|
| Aegean Airlines | Too big | Too big |
| Air Canada | Too tall (10.5" > 8") | Too big |
| Air France | Too big | Too big |
| Air New Zealand | No cabin pets | No cabin pets |
| Air Transat | Too big | Too big |
| Alaska Airlines | Too big | Too big |
| Alaska Horizon (Horizon Air) | Too big | Too big |
| Allegiant Air | Exact fit | Flexes — 0.5" over |
| American Airlines | Too big | Too big |
| American Eagle (regional, incl. Republic Airways) | Too big | Too big |
| ANA (All Nippon Airways) | No cabin pets | No cabin pets |
| Austrian Airlines | Too tall (10.5" > 9.1") | Flexes — 2.4" over |
| Avelo Airlines | Too big | Too big |
| Avianca | Too tall (10.5" > 10") | Flexes — 1.5" 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 | Too tall (10.5" > 9.1") | Flexes — 2.4" over |
| Cape Air | Too tall (10.5" > 8.5") | Too big |
| Cathay Pacific | No cabin pets | No cabin pets |
| China Airlines | No cabin pets | No cabin pets |
| Contour Airlines | Too tall (10.5" > 10") | Flexes — 1.5" over |
| Delta Air Lines | Too big | Too big |
| 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 | Fits | Flexes — 0.5" over |
| GOL Linhas Aéreas | Too big | Too big |
| Hawaiian Airlines | Too big | Too big |
| Iberia | Too tall (10.5" > 9.8") | Too big |
| ITA Airways | Too tall (10.5" > 9.1") | Flexes — 2.4" over |
| Japan Airlines | No cabin pets | No cabin pets |
| JetBlue | Too tall (10.5" > 8.5") | Too big |
| JSX | Exact fit | Too big |
| KLM Royal Dutch Airlines | Too big | Too big |
| Korean Air | Too tall (10.5" > 7.5") | Too big |
| Lufthansa | Too tall (10.5" > 9.1") | Flexes — 2.4" over |
| Norwegian | Too big | Too big |
| Porter Airlines | Exact fit | Flexes — 1" over |
| Qantas | No cabin pets | No cabin pets |
| Qatar Airways | No cabin pets | No cabin pets |
| Royal Air Maroc | Too tall (10.5" > 7.9") | Flexes — 3.6" 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 | Too tall (10.5" > 8.5") | Flexes — 3" over |
| Sun Country Airlines | Too tall (10.5" > 9") | Too big |
| Swiss International Air Lines | Too tall (10.5" > 9.1") | Flexes — 2.4" over |
| TAP Air Portugal | Too big | Too big |
| Turkish Airlines | Too big | Too big |
| United Airlines | Too big | Too big |
| Virgin Atlantic | No cabin pets | No cabin pets |
| Volaris | Too big | Too big |
| Vueling | Too tall (10.5" > 8.3") | Too big |
| WestJet | Too big | Too big |
Which should you buy?
The Diggs Passenger — it is within the published limit of 4 of the 43 airlines with a published cabin limit, against 0 for the SturdiBag Pro (Large, Flexible Height). That is the whole verdict on airline fit; real under-seat space still varies by aircraft and seat.
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Choose the Diggs Passenger if…
Diggs has discontinued this carrier. The Amazon link below goes to comparable carriers, not this exact bag.
- Structured, well-ventilated design; sits within the 18×11×11 airlines but its 10.5" height rules out the 8.5" airlines.
- It clears 4 of 43 airlines with a published cabin limit outright — more than the SturdiBag Pro (Large, Flexible Height).
- Diggs publishes no pet-size limit for this one — measure your pet and compare against the interior before you choose. How →
Choose the SturdiBag Pro (Large, Flexible Height) if…
- The flexible-height top is the whole point — it compresses down to slide under lower seats, then springs back. A common pick for the 8.5" airlines (compresses; verify for your specific seat).
- It clears 0 of 43 airlines with a published cabin limit outright.
- SturdiBag publishes no pet-size limit for this one — measure your pet and compare against the interior before you choose. How →
Full profiles: Diggs Passenger · SturdiBag Pro (Large, Flexible Height) · best carriers ranked · all carriers
Common questions
Which fits more airlines, the Diggs Passenger or the SturdiBag Pro (Large, Flexible Height)?
The Diggs Passenger — it's within the published limit of 4 of the 43 airlines with a published cabin limit, against 0 for the other. Real under-seat space still varies by aircraft.
What's the size difference?
Diggs Passenger: 17 × 12 × 10.5 in. SturdiBag Pro (Large, Flexible Height): 18 × 11.5 × 11.5 in. Height is the strict dimension under a seat, and the Diggs Passenger 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.