One Week Carry-On Only: What Fits

No waiting at the baggage belt. No checked bag that gets lost. No overweight fees. No dragging a suitcase across cobblestones.

Once you travel carry-on only, you never go back. And most people who try it for the first time ask themselves: why didn’t I do this sooner?

What the dimensions actually mean — and which airlines allow what

The big question first: what counts as carry-on?

Ryanair: 40 × 20 × 25 cm free (small bag). 55 × 40 × 20 cm with a fee (cabin bag with overhead access). easyJet: 45 × 36 × 20 cm cabin bag (overhead bin), with a fee. Lufthansa / Austrian / SWISS: 55 × 40 × 23 cm, max 8 kg. Eurowings: 55 × 40 × 23 cm on full-fare tickets; restricted on basic fares.

The differences are real. If you fly multiple airlines, check each one’s rules. A backpack that fits Lufthansa may be stopped at Ryanair.

What actually fits in a carry-on backpack

The standard 40 × 20 × 25 cm sounds small. It isn’t. Here’s what fits — tested, not theoretical.

Clothes for 7 days:

5 t-shirts or light tops (roll them, don’t fold)
2 pairs of trousers or 1 pair of trousers + 1 shorts
1 fleece or light jacket (handles temperatures down to about 10°C)
5 underwear
3–4 pairs of socks
1 evening outfit if needed (a simple shirt or small dress)

This works because you wash as you go. Hotels have clotheslines or a handwashing sink. Laundry services in Asia, Central America, and Southern Europe are everywhere and cheap — a week’s worth of washing and folding for €5–10.

Shoes: the biggest packing problem

Shoes take disproportionate space. The efficient solution: one pair that does everything. Good sneakers or leather sneakers that work for both day and evening. Flip-flops or sandals come along — they weigh almost nothing.

Leave your favorite shoes at home and bring only the most versatile pair. This is the hardest packing decision — and also the most important.

Tech: keep it compact

Charging cables rolled up in a small pouch
Universal adapter if needed (one, not several)
Headphones (in-ear or wired — not a large over-ear pair)
Power bank (10,000 mAh is enough, weighs about 200g)
Laptop or tablet if necessary — this is the biggest variable in weight

What to leave at home — and why

Full-size hairdryer Hotels have them. If not: buying one costs €15 and you can leave it behind. Still cheaper than a bag fee.

More than one book E-reader or the Kindle app on your phone. One physical book if it’s a favorite — two is too many.

“Just in case” clothes The jacket in case it gets cold. The dress in case you go somewhere fancy. The hiking shoes in case you hike. Nine times out of ten, these stay packed. Leave them at home.

Full-size perfume Travel format. Or buy a small bottle at your destination.

The 100ml rule — used smartly

Liquids in carry-on: max 100ml per container, everything in a transparent 1-liter bag. Most people know this.

What many don’t know: small refillable travel containers cost €5–10 for a set. Decant shampoo, conditioner, shower gel, sunscreen — all into the little bottles. That’s enough for a week easily.

With a well-packed backpack, security also goes faster — more tips in our guide 7 Airport Tricks That Save Time.

Which backpacks actually work

Not every backpack passes every gate check. What matters:

Shape stability: Soft bags expand and get stopped at the gate
Clear dimensions: Buy backpacks where the manufacturer states airline compliance
Internal organization: Compartments for tech, clothes, documents — everything reachable quickly

Reliable models: Osprey Daylite (20L, fits almost every overhead bin), Cabin Zero 28L (light, soft, foldable), Aer Go Pack (more structured, good for tech). All are well-organized inside and stick to their stated dimensions.

How to pack correctly

The order makes a difference:

Heaviest things (tech, shoes) at the bottom and close to your back
Clothes rolled not folded — saves 20–30% space
Small items (cables, toiletries) into side pockets or on top
Jacket last — or wear it while boarding

Try it once. You’ll never check a bag for a short trip again. And Zercy shows you right in the flight search which airlines include carry-on in the base fare.

Frequently Asked Questions

What can you realistically pack in a carry-on for a full week?

Yes. The prerequisite: pack deliberately and be willing to wash once along the way. For a week-long city trip or beach vacation in a warm climate, you need significantly less than you think. It gets harder for ski trips or very formal occasions — but for the majority of short trips: no problem at all.

Which airline has the most generous carry-on rules?

On long-haul: usually full-service airlines like Lufthansa, British Airways, or Singapore Airlines (55 × 40 × 23 cm, 8–12 kg). On short-haul: low-cost carriers are stricter. Ryanair has the tightest rules — 40 × 20 × 25 cm free. A Cabin Zero 28L backpack (approx. 45 × 36 × 20 cm) fits most airlines’ overhead bin dimensions.

What if my backpack ends up too full?

Pack earlier — not the night before, but 2–3 days out. Whatever you’d miss, pack. Whatever is a “maybe,” leave home. If it’s still too full: take one fewer clothing item. Strict but effective.

How do you manage carry-on only on longer trips of 2–3 weeks?

Yes, with adjustments. For 2–3 weeks or a longer trip: either wash strategically (laundromat every 5–7 days), or buy cheap clothes at your destination and leave them behind. Many long-term travelers do exactly this — deliberately own less, be freer.

One Week, Carry-On Only: What Actually Fits