How many cubic feet is standard luggage

Quick advice: Pick a carry-on sized at 22 × 14 × 9 inches (about 45 liters) for cabin use; choose checked suitcases in the 25–28 inch range when you need between 70 and 110 liters of capacity.

Typical examples: A common cabin case 22 × 14 × 9 in = ~2772 in³ ≈ 45 L. A medium checked 25 × 18 × 10 in = 4500 in³ ≈ 74 L. A large 28 × 20 × 12 in = 6720 in³ ≈ 110 L. Use these figures when comparing brands.

Airline limits to watch: Most carriers accept cabin pieces up to 22 × 14 × 9 inches and count checked bags by linear size (length + width + height) with a common ceiling of 62 inches (~158 cm); typical free checked weight is 23 kg / 50 lb.

Measure and calculate: To estimate volume from metric measurements: liters = (length_cm × width_cm × height_cm) / 1000. Measure packed external dimensions, then compare to airline allowances and the manufacturer’s published capacity in liters.

Packing tips: Opt for soft-sided cases when you need a few extra liters, use compression cubes to increase usable space, and check manufacturer liter ratings before buying to ensure the case matches your trip profile.

Measure a suitcase to get volume in ft³

Measure external length (L), width (W) and depth (D) in inches; include wheels, fixed handles and external pockets. Multiply L × W × D, then divide the product by 1,728 to obtain volume in ft³ (imperial cubic units used for packing and airline size limits).

1. External dimensions for airline or shipping rules:
   • Measure at the longest points for length and width.
   • Measure depth from rigid back to outermost face (include wheels/feet thickness).
   • Example: 28″ × 20″ × 12″ → 6,720 in³ ÷ 1,728 = 3.89 ft³.
2. Usable internal capacity (what you can actually pack):
   • Open main compartment and measure internal L, W, D (exclude inner pockets and divider thickness).
   • Soft-sided cases: compress to a representative packing pressure (squeeze to a realistic packed profile) before measuring depth.
   • Example: interior 22″ × 14″ × 9″ → 2,772 in³ ÷ 1,728 = 1.60 ft³ usable.
3. Adjustments for shape:
   • Rounded corners/tapered tops: measure depth at three points (center + two sides), use average depth; subtract ~5–12% from rectangular result depending on curvature severity.
   • Expandable sections: measure twice (collapsed and expanded); use expanded figure for packing limit, collapsed for storage/airline compliance if required.
4. Quick checks and verification:
   • If you need more precision, measure interior with foam blocks or flexible filler to calculate displaced volume, then convert from in³ to ft³ by dividing by 1,728.
   • Compare external vs internal volume; expect external to exceed internal by 8–15% on hard shells and 10–25% on soft shells due to structure and hardware.

Choose a case that matches your target packed volume and organization needs; see best luggage for traveling in greece for travel-specific models and best luggage organizer set for compartment solutions.

Convert dimensions (inches/cm) into ft³ for carry-on vs checked

Target volumes: aim for 1.5–2.0 ft³ (~42.5–56.6 L) for carry-on; 5–9 ft³ (~142–255 L) for larger checked bags.

Conversion (inches): multiply length × width × height (in inches) = cubic inches; divide by 1728 (12³) to get ft³. Example formula: ft³ = (L×W×H) / 1728.

Conversion (cm): multiply L×W×H (in cm) = cm³; divide by 28,316.8466 to get ft³. Example formula: ft³ = (L×W×H) / 28,316.8466.

Worked example 1 (carry-on): 22 × 14 × 9 in = 2,772 in³ → 2,772 / 1,728 = 1.603 ft³ (~45.4 L).

Worked example 2 (metric carry-on): 55 × 40 × 20 cm = 44,000 cm³ → 44,000 / 28,316.8466 = 1.553 ft³ (~44.0 L).

Worked example 3 (checked): 32 × 22 × 14 in = 9,856 in³ → 9,856 / 1,728 = 5.703 ft³ (~161.4 L).

Quick practical notes: add 2–4 in to depth when comparing against airline external-size caps to account for wheels and handles; soft-sided bags may yield ~5–10% extra usable internal volume but airlines measure outside dimensions. Typical linear-size limits: checked bags often capped at 62 in (158 cm) combined (L+W+H); carry-on combined dimensions commonly near 45 in (115 cm).

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Translate airline linear size limits into volume to estimate fees

Assume the carrier’s linear maximum S (length+width+height); use a practical bag ratio (width ≈ 0.6×length, depth ≈ 0.4×length) and apply this formula to estimate internal liters: Volume (L) ≈ 0.0004916 × S³ when S is in inches. For S in centimetres use Volume (L) ≈ 0.00003000 × S³.

Quick formula and tolerance

Coefficient range for common shapes: 0.00042–0.00056 × S³ (L) to cover slimmer or deeper designs. Convert to other units: 1 L = 0.0353147 ft³ (use ft³ only for display); 1 in³ = 0.016387 L.

Examples and practical rules

S = 62 in (158 cm) → ≈117 L (≈4.14 ft³) with the recommended ratio; realistic range ≈110–135 L depending on shape. S = 80 in → ≈252 L (≈8.9 ft³). Add a 10–15% safety margin for shell thickness, wheels and external trim when deciding if a bag will trigger oversize fees. If estimated volume (or S itself) approaches the airline limit, choose a bag whose measured sum is 1–2 in (2–5 cm) below the published maximum to avoid surcharges; when in doubt, measure the bag fully loaded and compare the linear sum before travel.

Volume examples for common suitcase sizes: 20″, 24″, 28″

Recommendation: pick 20″ for short trips, 24″ for week-long travel, 28″ for extended or shared use. Representative external boxes and usable internal capacity (allowing for shell, wheels, and pockets): 20″ = 20×14×9 in → 2,520 in³ → ~41 L raw → ~31 L usable; 24″ = 24×16×11 in → 4,224 in³ → ~69 L raw → ~52 L usable; 28″ = 28×18×13 in → 6,552 in³ → ~107 L raw → ~86 L usable.

Item-capacity guide (approximate, based on recommended usable volume): 20″ – 2–3 shirts, 1–2 trousers/skirts, 3–4 sets underwear/ socks, 1 pair shoes, 1L toiletry kit, one small electronics bag; 24″ – 5 shirts, 2–3 trousers/skirts, 1 light jacket, 2 pairs shoes, 1–2L toiletries, packing cubes (2); 28″ – 8–10 shirts, 4–6 bottoms, 2–3 shoes, bulky jacket, 3–4L toiletries, room for souvenirs.

Packing tips tied to size: for 20″ favor rolling and single-compression bags, prioritize outfit coordination and limit bulky items; for 24″ use two medium packing cubes (clothes / socks & intimates), place shoes in corners and toiletries in a sealed pouch; for 28″ reserve one compartment for heavier items near wheels, use an expansion zipper only for light items to avoid overweight charges.

Selection checklist: choose 20″ when carry-on allowance is required and you need minimal outfits; choose 24″ if you want checked convenience with moderate packing margin; choose 28″ when transporting bulky gear or packing for 7–14 days. When comparing models, subtract ~15–25% from advertised external volume to estimate realistic usable space.