bag vs limit
2.2" to spareTopo Designs Rover Pack Mini
13.5 × 8.5 × 3.75 inEnormous margin against every limit here, and it looks like a normal bag rather than travel gear. Ten litres is a daybag though, not a travel bag.
Aer Lingus allows a cabin bag of 55 × 40 × 24 cm — 21.7 × 15.7 × 9.4 inches — and weighs it at 10 kg (22 lb), which most US carriers never do. The under-seat item is 40 × 30 × 20 cm.
Fare class: Not published per fare tier — the allowance is set by aircraft and service type, not by Saver, Plus or Advantage.
The regional trap is gone. Aer Lingus Regional — flights EI 3000–3999, operated by Emerald Airlines — used to allow only 48 × 33 × 20 cm at 7 kg, and that 7 kg applied to a whole journey that touched a regional leg. Aer Lingus now states the allowance is the same across all its European flights, regional included. We listed the old regional limit until October 2026 and have removed it. Its personal item at 40 × 30 × 20 cm is now among the more generous here, not the smallest.
Measure the outside, wheels and handles included — that’s what they measure at the gate.
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Enormous margin against every limit here, and it looks like a normal bag rather than travel gear. Ten litres is a daybag though, not a travel bag.
The anti-theft option that actually fits — slash-resistant panels, locking zips, RFID pocket, and a 13-inch laptop sleeve, all inside United’s width.
Pacsafe’s own site is JavaScript-gated, so this comes from a retailer spec rather than the brand. The 0.2 inches of width margin rests on that number.
The most margin of anything here — comfortably inside United’s brutal 17 × 10 × 9 and inside the budget carriers’ 18 × 14 × 8 too. Structured neoprene that holds its shape instead of sagging.
Buy the MEDIUM. The Large is 16.5 × 11 × 9 and fails United on width.
The cheapest bag here we can fully stand behind. Cabin Max publishes 40 × 25 × 20 cm as the external size, and 40 × 25 × 20 works out to exactly the 20 litres they claim — when the arithmetic agrees with the marketing, the numbers are usually real. No wheels, so the usual “does that include the wheels” ambiguity doesn’t apply. Three-year warranty.
9.84 inches against United’s 10-inch limit is about a sixth of an inch of margin. It’s a soft bag and it will bulge — pack it full and it may not gauge.
Sold as a “17x10x9” bag but the manufacturer’s own spec is 40 × 25 × 20 cm — meaningfully smaller than the limit, which is exactly what you want. Clears United and the budget carriers both, for under thirty dollars.
At 0.77 lb this is a thin packable, not a structured daypack. Treat it as a very good backup bag rather than your only one.
A rare expandable that stays legal even when expanded — 5.9 inches deep collapsed, 7.9 expanded, and still inside United’s limit either way.
Don’t confuse this with COSCOOA’s expandable tote, which grows to 13 inches wide and busts United.
The only bag we verified that fits United and still takes a genuine 15-inch laptop. Military-grade build from a brand that makes packs for people who abuse them.
Only a quarter inch of width margin — don’t overstuff it. Also 8.5 inches deep, so it misses the budget carriers’ 8-inch limit.
55 × 40 × 24 cm, which is 21.7 × 15.7 × 9.4 inches, up to 10 kg (22 lb).
Yes — 40 × 30 × 20 cm, or 15.7 × 11.8 × 7.9 inches. It goes under the seat in front of you.
No — it is 0.3 inches over. Aer Lingus allows 21.7 × 15.7 × 9.4 inches, and the standard US 22 × 14 × 9 does not fit inside that.
Not published per fare tier — the allowance is set by aircraft and service type, not by Saver, Plus or Advantage.
Of the bags we track, 8 of 16 carry-ons fit the cabin limit and 7 of 25 personal items fit the under-seat limit. All of them are under the weight limit empty.
Manufacturers publish dimensions inconsistently, and a “20-inch” spinner is almost never 20 inches once you count the wheels. Where a brand states dimensions including wheels and handles, that’s the number we use. Where it only publishes the case, we say so on the card. Airlines measure the outside of your bag — wheels, handles, straps and all. Anything marked borderline is down to the gate agent, and remember that a soft bag squashes into a sizer while a hard shell won’t.
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Limits verified October 2026 against each carrier’s published policy. Airlines change these without notice — always confirm before you fly. Spirit Airlines ceased operations on 2 May 2026 and is no longer listed.
Airline Bag Size Checker v1.0.19 · last updated 2026-10-20