Sherpa Original Deluxe (Large) 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. Sherpa Original Deluxe (Large) is 19 × 11.75 × 11.5 in; SturdiBag Pro (Large, Flexible Height) is 18 × 11.5 × 11.5 in.
Side by side
| Property | Sherpa Original Deluxe (Large) | SturdiBag Pro (Large, Flexible Height) |
|---|---|---|
| External size (L×W×H) | 19 × 11.75 × 11.5 in | 18 × 11.5 × 11.5 in |
| Type | soft-sided · flexible height | soft-sided · flexible height |
| Pet weight | up to ~22 lb | — |
| Airlines it fits outright | 0 of 12 | 0 of 12 |
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 | Original Deluxe (Large) | Pro (Large, Flexible Height) |
|---|---|---|
| Delta Air Lines | Too big | Too big |
| JetBlue | Too big | Too big |
| American Airlines | Too big | Too big |
| United Airlines | Too big | Too big |
| Southwest Airlines | Too big | Flexes — check height |
| Alaska Airlines | Too big | Too big |
| Frontier Airlines | Too big | Flexes — check height |
| Air Canada | Too big | Too big |
| Allegiant Air | Too big | Flexes — check height |
| Sun Country Airlines | Too big | Too big |
| Hawaiian Airlines | Too big | Too big |
| Breeze Airways | Too big | Too big |
⚠️ "Fits" means within the published maximum — real under-seat space varies by aircraft and seat. See why →
Choose the Sherpa Original Deluxe (Large) if…
- Larger dog size; too tall for the 8.5" airlines even flexed — best on the 11" airlines (Delta, American, United).
- It clears 0 of 12 tracked airlines outright.
- Your pet is under ~22 lb.
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 12 tracked airlines outright.
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