40x30x20 cm in Inches: Cabin Bag Size Guide

40 x 30 x 20 cm is about 15.7 x 11.8 x 7.9 inches. This size is a common limit for a small cabin or under-seat bag, so people often search for it before they buy a bag or pack for a flight. Below is the conversion, how to measure your bag, and the cabin-size backpacks in the BuyerFriends shop.

Centimetres to inches

To convert, divide centimetres by 2.54. Here are common bag dimensions:

Centimetres	Inches
40 x 30 x 20 cm	15.7 x 11.8 x 7.9 in
40 x 25 x 20 cm	15.7 x 9.8 x 7.9 in
40 x 20 x 25 cm	15.7 x 7.9 x 9.8 in
45 x 36 x 20 cm	17.7 x 14.2 x 7.9 in
55 x 40 x 20 cm	21.7 x 15.7 x 7.9 in

Cabin-size backpacks at BuyerFriends

Each card shows the price and a line from the product’s own page. Check the dimensions on the product page before you order.

Cabin-Size Travel Backpack, 40x30x20cm$47.47This travel backpack is sized at 40x30x20cm to meet common airline cabin luggage size requirements.

40x30x20cm Cabin Travel Backpack, Ryanair-Compliant Size$40.65This travel backpack measures 40x30x20cm, sized to meet Ryanair's cabin baggage dimension requirements.

Waterproof Business Laptop Backpack, 40x30x20cm$54.58Waterproof Business Laptop Backpack, 40x30x20cm

Women's Cabin-Size Travel Backpack, 40x20x25cm$62.40This backpack is sized at 40x20x25cm to meet common airline cabin luggage requirements.

How to measure a bag for a flight

Measure the full bag, including wheels, handles, pockets and any items sticking out.
Measure when the bag is full. Soft bags can bulge past the listed size.
Use the outside measurement, not the inside space.
Check which dimension is which. Airlines list height, width and depth, and a bag that is slightly over in one direction can still be refused.

Always check your airline

Cabin and under-seat limits differ between airlines, between fare types, and they change. Check your airline’s current rules for the exact size and weight before you fly. A size listed on a product page is the product’s measurement, not a promise that an airline will accept it.

Tips for packing a small cabin bag

Pack heavy items near the back panel so the bag keeps its shape.
Use packing cubes to compress clothing.
Keep documents, chargers and valuables in an easy-access front pocket.
Wear your bulkiest layers on the plane.

Shipping and returns

BuyerFriends ships to US addresses with free standard shipping and 30-day returns. Items ship from supplier warehouses, so most orders arrive in 10 to 20 business days. Order early if you need them for a date. See our shipping policy and returns policy.

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