Measure length, width, and depth to find your bag's total size

Luggage size is measured by adding together the length, width, and depth of the bag in inches or centimeters. Airlines and hotels use this total to decide whether your bag fits their limits. A soft-sided bag that bulges when packed may measure larger than when empty, so measure it in the condition you'll actually use it — stuffed and zipped shut.

You need a measuring tape or ruler, a flat surface, and about two minutes. The measurement itself is straightforward, but the tricky part is knowing where to measure on an oddly shaped bag. Most luggage has a clear rectangular body, but handles, wheels, and pockets can confuse where the actual dimensions start and stop.

Key Takeaways

  • Measure the length (top to bottom), width (side to side), and depth (front to back) of your packed bag, then add all three numbers together to get the total size airlines use.
  • Measure from the outermost point of the bag itself, not including handles or wheels, which airlines do not count toward the limit.
  • Soft-sided bags should be measured when fully packed and zipped, because the actual dimensions change as you fill them.
  • Write down your bag's measurements and keep them with your travel documents so you know whether it meets each airline or hotel's size rules.

Gather your measuring tools and prepare the bag

Use a soft measuring tape (the kind tailors use) or a rigid ruler. A soft tape is easier because it bends around corners, but a ruler works fine if you measure each side separately. Lay your bag on a flat, hard surface like a table or floor — not on a bed or couch, where it will sink and give you a false reading.

If you're measuring a soft-sided bag, pack it the way you actually plan to travel. Zip it shut and let it sit for a minute so it settles into its final shape. If you measure an empty soft bag, the dimensions will be smaller than what you'll actually travel with, and you might find out too late that your packed bag exceeds the airline's limit.

For hard-sided luggage, the bag's shape is fixed, so you can measure it empty or full — the dimensions won't change. Still, place it on a flat surface and make sure it's sitting level, not tilted or leaning.

Measure the three dimensions correctly

Length is the distance from the top of the bag to the bottom. Place your measuring tape at the highest point of the bag (usually the top of the handle area, but measure the bag itself, not the handle) and run it straight down to the lowest point. Write this number down.

Width is the distance from the left side of the bag to the right side. Measure across the widest part of the bag at its middle. This is usually straightforward on a rectangular bag, but on bags with curved sides, measure the widest point.

Depth is how thick the bag is from front to back. Measure from the front surface of the bag to the back surface. On a bag with wheels, measure from the front to the back of the main body, not including the wheels that stick out.

Measure in inches or centimeters — whichever your airline or hotel uses. If you measure in inches and need centimeters, multiply by 2.54. If you measure in centimeters and need inches, divide by 2.54.

Know what to include and what to exclude

Measure the bag itself — the actual fabric or plastic shell. Do not include handles, straps, or wheels in your measurements. Handles stick up above the bag, and wheels stick out below it, but airlines measure the bag's body only. If your bag has a handle pocket on top, measure to the outside of that pocket, since it's part of the bag's structure.

If your bag has expandable sides or a zipper that lets you make it bigger, measure it in the expanded position if you plan to use that expansion. Some bags can grow by an inch or two when you unzip the sides — that counts as part of your bag's size.

Pockets on the outside of the bag are part of the bag, so if a pocket bulges out, measure to the bulge. Interior pockets do not add to the outside dimensions, so ignore them.

Add the three numbers to get your total size

Once you have length, width, and depth, add them together. For example, if your bag measures 22 inches long, 14 inches wide, and 9 inches deep, your total is 22 + 14 + 9 = 45 inches. This is the number airlines and hotels will ask for when they state their size limits.

Airlines often phrase limits as "62 inches total" or "158 centimeters total" — that's the sum of all three dimensions. Some airlines also set separate limits on individual dimensions (like "no longer than 22 inches"), so check both the total and any individual limits before you book.

Write your bag's measurements on a label and tape it inside the bag, or keep a photo of your measurements in your phone. If you travel often with the same bag, you won't have to measure it again.

Common mistakes to avoid when measuring

The most common error is including the handle or wheels. Handles can add 4 to 6 inches to the length if you measure from the top of the handle instead of the top of the bag. Wheels add 2 to 3 inches to the depth. Measure the bag's body only, and you'll get the number airlines actually use.

Another mistake is measuring a soft bag when it's empty or only partially packed. An empty duffel or rolling bag can be 2 to 4 inches smaller in one or more dimensions than when it's stuffed. If you're trying to figure out whether your packed bag will fit, measure it packed.

Don't measure at an angle or on an uneven surface. The bag should sit flat and level, and your measuring tape should run straight across, not diagonally. A diagonal measurement will be longer than the true dimension and give you a false reading.

Frequently Asked Questions

Do I measure the bag with or without wheels?

Measure the bag's body without including the wheels. Wheels stick out below the bag and are not counted in the airline's size limit. Measure from the bottom of the bag's main structure, not from the bottom of the wheels.

What if my bag is soft-sided and changes shape when I pack it?

Measure it in the packed state you'll actually travel with. Soft bags expand as you fill them, so an empty measurement won't tell you whether your packed bag meets the airline's limit. Pack it, zip it, and measure it that way.

Do handles count toward the size limit?

No. Handles are not included in the measurement. Measure from the top of the bag's body, not from the top of the handle. The same goes for straps, pockets, and any other attachments — only the main bag structure counts.

How do I measure a bag with an expandable section?

Measure it in the expanded position if you plan to use that expansion when you travel. If the bag has a zipper that lets the sides bulge out, unzip it and measure the bag at its largest size. That's the dimension you need to report.

Can I measure in centimeters if the airline asks for inches?

Yes, but convert the number. Multiply centimeters by 0.39 to get inches, or multiply inches by 2.54 to get centimeters. Write down both measurements so you have them ready for any airline or hotel.