Linear Inches Calculator
Linear inches is just length + width + height — the number airlines size your bag by. Enter the three dimensions in inches or centimeters and see the total, plus how it stacks up against the standard 62 in checked-bag and 45 in carry-on limits.
Example: with Length (longest side) 27 · Width 21 · Height / depth 14 · Unit inches → Linear inches: 62 linear inches (157.5 cm).
- Checked-bag check (62 in)Exactly at the 62 in checked-bag limit — OK, no margin
- Carry-on check (45 in)17.0 in over the 45 in carry-on standard (22 × 14 × 9 in) — gate check likely
Computed by the calculator below using its default values. Change any input to see your own numbers.
Linear inches = length + width + height, wheels and handles included. Nearly all US airlines cap standard checked bags at 62 linear inches (158 cm) and carry-ons at 45 linear inches (22 × 14 × 9 in).
Why airlines add three numbers together
Cargo holds and overhead bins fill by volume, but measuring true volume at a check-in counter is slow. Linear inches — length plus width plus height — is the industry's quick proxy: one tape-measure pass per side, one sum, one limit. The near-universal standard is 62 linear inches (158 cm) for a checked bag and 45 linear inches for a domestic carry-on, usually expressed as 22 × 14 × 9 in. Airlines measure the outside of the bag, wheels, handles, and side pockets included.
A typical 'large' 27 in spinner runs right at 62 linear inches once you include wheels — which is why manufacturers advertise the shell height and quietly hope you do not add the hardware. Measure your actual packed bag standing naturally, at its widest points.
What happens over the line
From 63 to 115 linear inches, most US carriers accept the bag with an oversize fee that commonly runs $100-$200 each way (on top of any weight penalty — the two fees stack). Above 115 linear inches, airlines generally refuse the item and point you to air cargo. Carry-ons over 45 in get gate-checked, which is free on legacy carriers but a paid surprise on many low-cost airlines.
How it’s calculated
Linear inches = length + width + height, measured at each dimension's widest point including wheels and handles. Centimeters convert at 1 in = 2.54 cm exactly (62 in = 157.5 cm; airlines round to 158 cm). Comparisons use the standard US limits: 62 linear in for checked bags and 45 linear in (22 × 14 × 9) for carry-ons.
Limits are the common US-carrier standard — international, regional, and low-cost airlines set their own (often smaller) caps, so verify your specific airline before flying.
Common airline size limits
| Category | Limit | Notes |
|---|---|---|
| Checked bag (standard) | 62 linear in / 158 cm | Nearly all US and most international carriers |
| Carry-on (US majors) | 45 linear in (22 × 14 × 9 in) | Low-cost carriers often smaller |
| Personal item | About 36 linear in | Varies widely; must fit under the seat |
| Oversize checked | 63-115 linear in | Accepted with an oversize fee |
| Over 115 linear in | Refused | Ship as air cargo or freight |
Contract-of-carriage baggage rules for major US airlines (American, Delta, United); check your carrier for exact figures.
Common mistakes
- Measuring the shell only — wheels, handles, and bulging pockets count, and they add 2-3 in on a spinner.
- Confusing linear inches with cubic volume; a 62 linear inch limit is a sum, not a multiplication.
- Measuring the bag empty: packed bags bow outward an inch or more on soft sides.
- Assuming 62 in is universal — some international and budget carriers cap lower, and personal-item rules differ per airline.
Frequently asked questions
How do I calculate linear inches?
Add the bag's length, width, and height: a 27 × 21 × 14 in suitcase is 62 linear inches. Measure each dimension at its widest point, including wheels and handles.
What is 62 linear inches in bag terms?
It is the standard checked-bag ceiling — for example 27 × 21 × 14 in, or 30 × 20 × 12. Any combination summing to 62 or less passes the size rule (weight is a separate limit, usually 50 lb).
Do wheels and handles count in linear inches?
Yes. Airlines measure the outermost points of the bag as it stands, so wheels, fixed handles, and stuffed outer pockets are all included. That typically adds 2-3 inches over the advertised shell size.
What happens if my bag is over 62 linear inches?
Between 63 and 115 linear inches you pay an oversize fee, commonly $100-$200 each way on US majors, stacked on any overweight fee. Over 115 linear inches most airlines refuse the bag entirely.
Is 158 cm the same limit as 62 inches?
Yes — 62 in × 2.54 = 157.5 cm, which airlines round to 158 cm in metric markets. If your bag's spec sheet is metric, keep the sum of the three sides at or under 158 cm.