Carry-on luggage: dimensions, weight and the 100 ml rule at security

Carry-on luggage flies in the cabin with you. The rules for it are stricter than for checked baggage: liquids, knives, food, and Duty Free purchases are screened separately. Below is a breakdown of what is allowed, with dimensions, weight, and the 100 ml rule (as of: 09/2026).

Most restrictions are tied to the size and weight of a single item. In addition, security checks the volume of liquids and sharp objects in your bag.

What you can take in carry-on luggage

💡 In short:

• The size of one item is set by the carrier: Lufthansa allows 55×40×23 cm, IATA recommends up to 56×45×25 cm.
• Weight depends on the carrier: Lufthansa allows up to 8 kg, Ryanair only lets a 40×30×20 cm bag through for free.
• Liquids: no more than 100 ml per container, all in one clear 1-liter bag.
• Liquid and dimension rules: 09/2026, verified on the European Commission website.

Some carriers allow outerwear, an umbrella, or a cane beyond the standard allowance. Check the airline's website for the list of such items and the rules for strollers.

Allowed weight and dimensions

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One piece of carry-on luggage is measured by the sum of its three dimensions. In economy class this is usually one item, in business class two. Some airlines make exceptions and state them in advance. Check the numbers on the carrier's website before buying a ticket (as of: 09/2026).

Weigh your bag at home and measure it with handles and wheels included. Ryanair's free size is 40×30×20 cm, anything larger requires priority boarding (as of: 09/2026, Ryanair rules). Lufthansa's 8 kg limit applies to the entire item (as of: 09/2026, Lufthansa rules). If the bag is heavier, you will have to move some items or check the bag for an extra fee.

Liquids and the 100 ml rule

AIIllustrative image: AI-generated

Liquids, gels, aerosols, and pastes are measured by the container volume, not by how much is left inside. On September 1, 2024, the European Commission introduced a temporary restriction for EU airports with C3 scanners (as of: 09/2026, European Commission website). At these airports the 100 ml per container limit also applies. It is not always clear in advance which scanner your airport has. The simple takeaway: take containers no larger than 100 ml and put them all in one clear 1-liter bag.

Medications and medical devices are allowed with a prescription and a doctor's note. Baby food in plastic containers is screened separately but usually allowed without volume restrictions. Keep the prescription handy so screening goes faster.

What you can put in your toiletry bag

Before your flight, go through your toiletry bag. A nail file and manicure tweezers are allowed if they are no longer than 6 cm. Creams, gels, and cleansers go into the liquids bag. Perfume in a container larger than 100 ml is not allowed on board: either switch to a smaller container or leave it at home.

Solid products are easier to bring. Eyeshadow, powder, pencil, and bar soap do not count as liquids. If you are carrying non-standard cosmetics, check your set on the carrier's website in advance.

Food and drinks in flight

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In-flight meals can be paid, and the quality does not suit everyone. Hence the question of what to bring on board. An empty plastic bottle can be filled with water at a dispenser after security, and sometimes flight attendants will do it for you. Food has no strict restrictions.

Take cookies, chocolate, nuts, fruit, and sandwiches with chicken, cheese, or beef. Products should not have a strong smell or release gas. Remember that yogurt, jam, and sauces count as liquids and go into the bag at security. Napkins and an empty trash bag will also come in handy on the trip.

Duty Free purchases

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Duty Free purchases have a separate rule. The store packs and seals them before departure. At a connection, security checks the seal and the receipt. If the seal is intact and the receipt is there, there are usually no problems. But there is no full guarantee: the decision is made by the security officer.

Buy your purchase before the final destination. That way alcohol and perfume do not cause trouble at connections and you are definitely bringing them home.

What is prohibited in carry-on luggage

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Before your flight, check the list of prohibited items. Sharp and cutting objects, tools, weapons, and hazardous substances are not allowed on board. Sharp scissors, knives, and screwdrivers go in checked baggage.

Liquids over 100 ml per container also stay at home. Following these rules saves you unnecessary stress at security. Air travel is considered one of the safest modes of transport, and these checks are for the safety of the passengers themselves.

⁉️🤔 Frequently asked questions

Can I take a 0.5 L bottle of water in carry-on luggage?

No, a container larger than 100 ml will be taken at security. An empty bottle can be filled after screening. On economy flights drinks are often paid, so your own bottle saves money and stress.

How many liquid items are allowed in one bag?

One clear 1-liter bag is allowed per passenger. Each container inside must be no larger than 100 ml. Pack items so the bag closes easily, and keep it handy: at security it is taken out separately.

What if my bag does not fit the size limit?

At the gate, the bag is either checked for an extra fee or you pay for priority boarding. The price depends on the carrier and fare. Measure your bag at home with handles and wheels included so you do not argue at the counter under pressure from the line.

Can I bring prescription medications?

Yes, medications are allowed with a prescription and a doctor's note, even beyond the 100 ml rule. Take enough medication for the entire route.

Do I need to take my laptop out of my bag?

Usually yes, the laptop is taken out of the bag and placed in a separate bin. At airports with new scanners it is sometimes left inside. Look at the signs at the security line and ask the officer so you do not hold up the line.

In short: what to take in carry-on luggage

Pack your bag to fit your carrier's free size: 40×30×20 cm for Ryanair (Ryanair rules) or 55×40×23 cm for Lufthansa (Lufthansa rules). If you only have cosmetics: take everything in mini containers and one 1-liter bag. If you are flying with a child: add baby food and, if needed, a stroller according to the carrier's rules. If you are bringing purchases: leave Duty Free for the last leg of the trip.

Before your flight, check the dimensions and liquid rules on the carrier's website. Checking the rules once is cheaper than paying for baggage at the airport. For unusual airports, read our breakdown of the world's most unusual airports.