𧳠Bag Size Checker
Will your bag fly? Check it against carry-on and personal-item limits.
Bag verdict
How to Use This Bag Checker
Measure your bag packed as you would fly, including wheels, handles, and bulging pockets, then enter length, width, and height in inches. The checker compares your bag against the two limits that matter: the 22 x 14 x 9 inch carry-on standard used by American, Delta, and United, and the 18 x 14 x 8 inch personal-item limit for under-seat bags. You get a verdict for each, plus linear inches for checked-bag math. Measure the real bag, not the product listing: manufacturers measure the shell, airlines measure the reality.
Pack the bag the way you will fly, then measure length, width, and height with a tape measure, wheels and handles included.
Enter the three dimensions in inches. Order does not matter; the checker sorts them against each limit.
Hit Check My Bag. Green means it fits the published limit; check the margin line to see how close it is.
If it is borderline, repack to 90 percent full and re-measure. Soft bags shrink; hard shells do not.
The Method: Three Numbers, Two Limits
Airlines publish limits per dimension because overhead bins and under-seat spaces are boxes, not volumes: a bag that is 25 inches long fails even if its total volume is small. The checker compares your longest side against the limit's longest side, middle against middle, shortest against shortest, which handles any measurement order you enter. Linear inches matter for checked bags, where the standard cap is 62 total inches before oversize fees kick in. The margin line shows your tightest dimension, because one bulging side is all it takes to fail a gate sizer. Note the honest caveat: these are the common US major-airline limits, and budget carriers publish smaller ones, so always confirm your specific airline before a trip where fees sting.
Worked Example
A roller bag measures 23 x 14.5 x 9.5 inches packed. Linear inches = 47. Against the carry-on limit: 23 > 22, so it fails as a carry-on despite being close. Against the personal-item limit it fails badly. Verdict: check it, or repack into something smaller. Now the same bag measured empty per the product page said "22-inch": the wheels added the fatal inch. This is the single most common gate surprise in air travel, and it is entirely preventable with a tape measure the night before. A soft duffel at 22 x 13 x 8 passes comfortably with room to spare.
Packing to Fit: Practical Tricks
Soft bags are adjustable luggage: cinch compression straps, move dense items to the center, and keep the outer faces flat so the bag presents its smallest profile to the sizer. Wear your bulkiest items: boots and jackets on your body do not count as bag dimensions. Use the personal-item allowance strategically; a tote with the overflow often beats one overstuffed carry-on. For the return trip, remember souvenirs expand the bag that fit perfectly on the way out; leave 10 percent slack or plan to check. And photograph your bag's measurements once: the numbers do not change, and you will reuse them for every future booking.
When the Rules Differ
Budget carriers are the strict exception: their free allowance is often just the personal item, and their carry-on fees at the gate exceed the online price, which is the business model working as designed. International flights add another layer, with many airlines using weight limits (often 7 to 10 kg for cabin bags) alongside size limits. Regional jets with small overhead bins may gate-check compliant bags anyway; that is free and your bag meets you at the jet bridge. Codeshare flights follow the operating carrier's rules, not the airline you booked with. The checker covers the standard US case; for anything exotic, the airline's baggage page is the final authority.
Packing Cubes and Organization
Packing cubes do not save space; they save sanity. The win is compartmentalization: clean versus worn, outfits by day, electronics separate from liquids. Compression cubes add modest space savings by squeezing air out, maybe 10-15 percent on bulky knits. Size the cubes to the bag: large cubes in a carry-on waste the corners, while medium cubes tile efficiently. Roll clothes instead of folding for knits and casual wear; fold structured shirts to avoid crease chaos. The 5-4-3-2-1 rule (5 tops, 4 bottoms, 3 shoes, 2 layers, 1 hat for a week) plus laundry beats overpacking every time. And keep one empty cube for dirty laundry; the separation is worth more than the space it takes.
The 62-Inch Rule: How Checked Bags Are Measured
Carry-on limits use three separate maximums, but checked bags use one combined number: linear inches, which is length plus width plus height. Most US airlines cap checked bags at 62 linear inches and 50 pounds. A bag measuring 30 by 20 by 12 inches is exactly 62, right at the limit. Go over and the oversize fee is brutal, typically $100 to $200 each way on major US carriers, which can exceed the price of the ticket it is riding on.
Weight and size are separate fees that stack. A 55-pound bag that is also 65 linear inches can attract both an overweight fee (usually $100) and an oversize fee on the same trip. This is why the calculator asks for all three dimensions: a bag that looks fine can fail on the sum. If you are close to either limit, weigh the packed bag on a bathroom scale and measure the sum before you leave, not at the counter.
Second Worked Example: The European Budget Airline Test
Your US carry-on measures 22 by 14 by 9 inches, which fits American and Delta. Now try it on a European budget carrier. Convert: 22 inches is 55.9 cm, so the bag is 56 by 36 by 23 cm. Ryanair's free small bag allowance is 40 by 20 by 25 cm, and even their paid priority cabin bag is 55 by 40 by 20 cm. Your bag fails both: too tall for priority, far too big for free. Enter the dimensions and the airline's limits above to see the verdict before you book.
The lesson is that there is no universal carry-on. US domestic limits are the most generous in the world; European and Asian budget carriers run smaller and enforce harder, sometimes with metal sizers at the gate and fees of 40 to 70 euros for failures. If you fly mixed itineraries, size for the strictest airline on the ticket.
Soft Bags Get a Free Inch; Hard Shells Do Not
A soft duffel or backpack can compress an inch or two when squeezed into a sizer, which is a genuine advantage at strict gates. A hard-shell suitcase cannot, so measure it honestly and assume zero give. Either way, measure the bag packed, including wheels, handles, and front pockets, because airlines measure the outermost points. The number-one sizer failure is a bag whose body fits but whose wheels push it half an inch over. That half inch is the most expensive half inch in travel.
The Personal Item Loophole
Most airlines allow a carry-on plus a personal item, typically around 18 by 14 by 8 inches, that fits under the seat. That second bag is free packing volume: a packed backpack plus a full-size carry-on can total 5 to 7 days of clothing. Budget carriers are the exception; some charge for anything beyond a small bag. Check both allowances before you pack, because the personal item is the difference between checking a bag and not.
Frequently Asked Questions
What are the standard carry-on dimensions?
The most common US limit is 22 x 14 x 9 inches, wheels and handles included. That is the rule at American, Delta, and United. Always measure the bag packed and standing, including wheels, because gate agents eyeball the bulkiest version of your bag, not the spec sheet version.
What is the personal item size limit?
Typically 18 x 14 x 8 inches, small enough to slide under the seat. Backpacks, totes, and laptop bags usually qualify. Budget airlines enforce this hardest: the free bag on a basic fare is the personal item, and an oversized one gets a gate fee. This checker compares your bag to both limits at once.
Do wheels count in bag measurements?
Yes, on every major airline. The published limits include wheels, handles, and any protruding pockets. A bag sold as "22-inch" often measures 23+ inches with wheels, which is exactly how people get flagged at the gate. Measure your actual bag with a tape measure, packed as you would fly.
What are linear inches?
Length plus width plus height, a single number airlines use for checked bags. The standard checked limit is 62 linear inches total. A 22 x 14 x 9 carry-on is 45 linear inches. The checker computes linear inches automatically so you can compare against any airline's published cap.
Why do bags get rejected at the gate?
Two reasons: size and fullness. A bag that fits the sizer empty can fail it when overstuffed, because soft bags bulge past the frame. Gate agents target bulging bags and rigid rollers that obviously exceed the sizer. Pack to 90 percent, compress soft bags, and keep the bulkiest side facing out when you test the fit at home.
Can I bring a backpack as a carry-on?
Yes, if it fits 22 x 14 x 9 inches. Most travel backpacks in the 35 to 45 liter range qualify; 60+ liter hiking packs usually do not. The personal-item category is where backpacks shine: a 20 to 25 liter daypack slides under most seats. Measure yours; liter ratings do not translate to inches reliably across brands.
Do airlines actually measure bags?
Rarely with a tape measure, constantly by eye. Gate agents develop a feel for oversized bags and pull them into the sizer frame. Full flights trigger stricter enforcement because overhead space is the real constraint. A bag one inch over might pass on an empty Tuesday flight and fail on a packed Friday one.
What is the difference between carry-on and personal item?
A carry-on goes in the overhead bin (22 x 14 x 9 inches) and a personal item goes under the seat (about 18 x 14 x 8). Basic economy fares on some airlines include only the personal item, so your "free" bag allowance depends on the ticket. The checker labels your bag against both so you know which fare it fits.