The Thule Aion is not a one-laptop backpack decision. The 28L works as the compact personal-item option with 32L overflow, while the 40L moves into carry-on work-travel territory where laptop fit, airline rules, and loaded comfort matter more.
That size split controls the purchase. Choose the 28L when compact carry is a priority. Choose the 40L when a standard 15.6-inch PC or 16-inch MacBook is traveling with work clothes and toiletries, and overhead bin use is acceptable.
Scorecard
The Thule Aion’s 83.31 DVSS Score and Excellent tier make it a strong first-pass candidate, but that score cannot prove the 40L laptop sleeve clears an MSI GS75 17-inch gaming laptop, cannot sharpen the 28L sleeve fit promise, and cannot turn 40L under-seat fit, strap comfort, or waxed-canvas surface wear into guarantees.
| Metric | Value |
|---|---|
| Date assessed | 27 Apr 2026 |
| DVSS Score | 83.31 |
| Satisfaction Tier | Excellent |
| Dissatisfaction Score | 11.50% |
| Critical Dissatisfaction Rate | 9.59% |
Based on buyer feedback patterns, not hands-on testing. See how this scoring works.
I work from verified carry reports — people who moved this bag through European airports at carry-on limits, commute with 13–16-inch laptops, 28L compact travel loads with Switches and battery banks, and 40L business trips where a 15.6-inch PC or 16-inch MacBook anchored the packing plan. The 9.59% critical dissatisfaction rate is attributable to size mismatch, laptop-fit limitations, loaded-carry discomfort, strap reliability concerns, and waxed-canvas surface wear — each of which is addressed in the sections below.
The score is only the first filter; the real purchase decision comes down to the 28L expansion panel, the 40L laptop sleeve, the 13 x 9.1 x 20.5-inch carry-on body, and the strap system under loaded travel conditions.
Quick Take
- Best For: Laptop travelers choosing between 28L personal-item carry and 40L carry-on work-travel capacity.
- Not For: 17-inch gaming laptops, guaranteed under-seat 40L use, all-day loaded walking, or 45L roller-case replacement.
- Top Strength: The Aion size split creates two clear laptop-travel options instead of one vague backpack choice.
- Main Limitation: The wrong size creates the problem: 28L can run short on travel capacity, while 40L can lose personal-item certainty.
Decision Matrix
| Your situation | What to consider | Why |
|---|---|---|
| A laptop, Switch, charging cables, battery banks, and two days of emergency clothes need compact carry | Thule Aion 28L | The 28L expands to 32L and keeps the compact personal-item option stronger than the 40L. |
| A 15.6-inch PC or 16-inch MacBook travels with business clothes and toiletries | Thule Aion 40L | The 40L sleeve and 13 x 9.1 x 20.5 inch body match carry-on work-travel use better than the 28L. |
| An MSI GS75 17-inch gaming laptop or thick oversized chassis is the main device | Compare larger laptop backpacks | The 40L sleeve can compress padding or pressure the zipper, and the 28L fit for thick devices is not established. |
| Chargers, cables, adapters, and bulky accessories exceed the built-in pockets | Add a tech pouch | The admin pockets work better for flat and small tech than over-ear Beats-style headphones or full-depth stash needs. |
| Camera body and lens carry becomes the main setup | See Best Camera Bags | The Aion material here supports laptop travel, not camera-body and lens protection. |
Does the laptop fit the right Aion size?
Screen size only gets part of the answer. The sleeve, padding, and zipper decide whether the laptop belongs in this backpack.
The 40L has the cleaner laptop line.
The Thule Aion laptop decision starts with the compartment, not the capacity: the 40L padded laptop and tablet compartment offers a cleaner fit for most standard 15.6-inch PC and 16-inch MacBook setups, while the 28L compartment still needs a sharper fit promise because thick or oversized devices do not have a confirmed fit.
The 40L padded laptop and tablet compartment keeps a standard 15.6-inch PC and a 16-inch MacBook in the cleaner slot. Still, an MSI GS75 17-inch gaming laptop changes the outcome — the sleeve padding can compress, the zipper can take pressure, and the electronics padding can intrude into the main clothing space.
The same 40L compartment behaves differently with a 12-inch laptop because the smaller device leaves room for compression cubes or other items — and that small-device upside does not carry over to larger chassis sizes.
The 28L sleeve needs a narrower promise.
The 28L laptop and tablet compartment can fit a laptop-plus-tablet setup, but the lack of a thick-device fit confirmation leaves the 28L outside the same level of certainty as the 40L’s standard 15.6-inch PC and 16-inch MacBook guidance.
That gap matters more than the trip plan. When a laptop misses the sleeve fit, the whole Aion decision shifts — the backpack can still hold travel items, while the device fit stays unresolved.
Is the Aion a personal item or a carry-on first?
The Aion gets easier to judge once size no longer means “more or less space.” Each variant changes the travel role before it changes the packing list.
The 28L protects the under-seat option.
The Thule Aion size split changes the travel role before it changes the packing list: the 28L body expands to 32L for compact personal-item carry, while the 40L body measures 13 x 9.1 x 20.5 inches, weighs 3.19 lb, and moves closer to carry-on use once predictable under-seat fit matters.
The 28L main compartment has a 4.72 x 13.78 x 17.72-inch body and an unexpanded internal cavity measuring approximately 18 x 12 x 6 inches. Hence, the 5.72–6.72-inch expanded width serves as overflow — not as permission to turn the pack into a larger travel bag.
The 28L main compartment can carry compact travel-tech loadouts such as a laptop, Switch, charging cables, battery banks, two days of emergency clothes, snacks, glasses, sunglasses, and a medium water bottle — or a CPAP, TURTL travel pillow, Fuji X100V, iPad, Kindle, chargers, and Anker 3-in-1 desk charger — but bulky multi-day clothing loads push the 28–32L format beyond its compact boundary.
The 40L moves toward overhead-bin use
The 40L body’s 13 x 9.1 x 20.5-inch size and 3.19 lb empty weight place it closer to carry-on use, and under-seat flexibility remains conditional on a not-full load, airline rules, and the smaller 4.72 x 13.78 x 17.72-inch mixed-listing figure not being used as clean 40L sizing.
The 40L main compartment can make sense for three to four days of business clothes, a 16-inch laptop, toiletries, and light clothing — but the same compartment stops short of replacing a 20-inch 45L rolling case when bulky sports clothing controls the load.
That size tradeoff is the decision in plain terms. The 28L gives up primary travel-bag capacity to keep compact carry cleaner. The 40L gains work-travel room but pushes decisions about airline and carry-on duration forward.
Where the pockets help, and where they stop
The Aion’s layout works best when tech items stay flat, small, and visible. Bulky accessories push the decision away from built-in pockets and toward complements.
Small tech stays in the system.
The Thule Aion pocket system works when tech stays flat and easy to separate: passport, wallet, travel documents, cables, chargers, phone, earbuds, and keys stay in the access flow — but over-ear Beats-style headphones, protected sunglasses storage, a light jacket, or a full-depth stash need to push the layout past its clean zone.
The 40L clamshell opening and light-colored interior make clothing, cables, travel documents, and small tech accessories easier to locate, but the shallow lip, mesh pocket, loaded flap, and roughly half-depth front pocket narrow the layout once containment or a light-jacket stash becomes the priority.
Bulky accessories break the pocket plan.
The 40L compression straps, detachable wet bag, mesh toiletry zip compartment, and full-length zip compartment keep clothing, toiletries, and wet items separated — but fiddly compression-strap fasteners can slow the same setup when quick repacking matters.
The 28L admin pocket system keeps earbuds, cables, phone, passport, wallet, and keys accessible without pulling the main compartment away from laptop-travel cargo. Still, over-ear Beats-style headphones and protected sunglasses storage push bulky accessory carry into a different solution.
A tech pouch becomes the clean complement when chargers, adapters, cables, or headphone storage start competing with the backpack’s built-in pockets. Without that complement, the pocket setup has to handle a job its depth and layout do not clearly cover.
The size split that creates regret.
The strongest reasons to pause all stem from asking one Aion size to do the other’s job. The limits are not random — they follow the same 28L-versus-40L split.
Seventeen inches changes the laptop fit.
The Thule Aion turns risky when the size split is expected to erase every edge case: a 17-inch gaming laptop can overwhelm the 40L sleeve, the 40L body can lose personal-item predictability, the 28L body can run out of one-bag travel space, and the waxed-canvas exterior can mark or fade in ways the care method cannot fully reset.
A large laptop fit needs more than a screen diagonal. The 40L has the cleaner standard-laptop fit, but the MSI GS75 17-inch gaming laptop has an oversized chassis that falls outside the safe claim.
Loaded carry has a time limit.
The 40L shoulder-strap carry system stays closer to airport movement and moderate backpack carry than long-haul load transfer, because the missing built-in hip strap leaves fully loaded comfort exposed beyond one or two hours, all-day city movement, 10 days of walking in Scandinavia, or shoulder-sensitive carry where trapezius pressure appears within five minutes.
The 28L fixed shoulder straps and adjustable cross strap match compact laptop-travel loads, and the Aion Sling Bag can act as a belt-strap complement — but the carry system stops being the clean choice once stowaway straps, proven hip-belt load transfer, a back panel one to two inches longer for a 6-foot user, or more comfortable grab handles become central.
Water and wear stay conditional.
The 28L internal waterproof section can separate papers, wet items, a swimsuit, or dirty clothes, and the recycled nylon waxed-canvas exterior has a defined care approach with a wet cloth, mild detergent, and air drying — but none of that turns the Aion into sealed electronics protection or makes stain recovery predictable across colors or production periods.
The 28L lockable zipper supports basic closure control, and the zipper systems across the Aion line can feel like a strength. Still, protruding zipper pulls, isolated backstrap failures, and clipped-strap failures keep theft resistance and long-term strap reliability outside the safe claim.
Buy or Skip the Thule Aion?
Buy the Thule Aion only after the size option matches the tech kit: the 28L is for compact personal-item travel with 32L overflow, while the 40L is for standard 15.6-inch PC or 16-inch MacBook work travel, where carry-on capacity matters more than guaranteed under-seat fit.
The safest Aion decision starts with the travel role: the 28L protects personal-item use when compact carry matters. At the same time, the 40L protects work-travel capacity when overhead-bin use is acceptable and under-seat fit does not need to be predictable across airlines.
Skip the Thule Aion when the main requirement is a 17-inch gaming laptop fit, a guaranteed personal-item 40L backpack, all-day loaded walking, 45L rolling-case replacement, sealed electronics protection, or camera-body and lens protection. Those needs point to a different Tech Carry option rather than a different reading of the same backpack.
Check the Price: The price decision should start with size, since the 28L and 40L solve different laptop travel problems.
- Thule Aion 28L — for compact personal-item laptop travel with 32L overflow.
- Thule Aion 40L — for carry-on work travel with standard 15.6-inch PC or 16-inch MacBook fit.
See More Options: These pages make more sense when the Aion size split does not match the setup.
- Best Small Laptop Backpacks — when the 28L feels close, but a broader compact laptop backpack comparison fits better.
- Best Medium-Size Laptop Backpacks — when the 28L feels close but a broader work, school, or everyday laptop backpack comparison fits better.
- Best Large Laptop Backpacks — when the 40L option matters more because travel-heavy tech carry or a larger laptop setup drives the decision.
- Best Tech Pouches — when chargers, cables, adapters, or bulky accessories exceed the Aion pocket layout.
