PackFitter
Packing Calculator & Fit Tool
Plan. Pack. Fly.
Last updated: March 2026
A 40L backpack fits within Ryanair's carry-on limit of 55 × 40 × 20 cm, though taller or wider builds at this size should be checked carefully. However, Ryanair only includes a small personal item (40 × 20 × 25 cm) for free on standard fares. To bring a 40L bag on board, you need to purchase priority boarding — which also gives you overhead bin access. Without it, your bag may be gate-checked and charged. Pre-purchasing priority online is significantly cheaper than paying at the gate.
Check if this will actually fit your trip →Your result depends on what you pack, not just the bag size.
Based on real clothing volumes and packing behavior
| Personal item (free) | 40 × 20 × 25 cm — must fit under the seat |
| Carry-on (priority only) | 55 × 40 × 20 cm (21.7 × 15.7 × 7.9 in) — requires paid priority boarding |
| Weight limit | 10 kg for carry-on; no stated weight limit for personal item |
| Enforcement | Strict — bags are measured at the gate; oversized items may be charged |
| Fit at 40L | A 40L backpack fits as a carry-on with priority boarding — too large for the free personal item slot |
A 40L backpack fits comfortably within Ryanair's carry-on limit of 55 × 40 × 20 cm. However, carry-on access is not included by default — you must purchase priority boarding (available online or at the gate, but cheaper online). Without priority, only a small personal item (40 × 20 × 25 cm) is allowed free. A 40L bag will not fit the personal item sizing frame. Ryanair enforces these limits consistently at the gate.
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Not sure if it'll all fit? Try the packing calculator →
This tool reflects real-world packing conditions, not just theoretical bag sizes. Results are based on typical clothing volumes, packing efficiency, and common travel setups.
Ryanair's carry-on limit is 55 × 40 × 20 cm, but carry-on access requires paid priority boarding. Without it, only a small personal item is free. A 40L bag should be treated as a carry-on on Ryanair. Final acceptance at the gate depends on packed external dimensions — not the bag's listed volume.
This is a planning tool, not a guarantee. Airline staff make the final call — packed shape, bag rigidity, and gate-day enforcement all play a role.