Michael Turner
Immediate recommendation: record the external length, width and height including wheels and any extended handles; keep the linear total at or below 158 cm (62 in) and the packed weight at or below 23 kg (50 lb) for most international economy tickets. If you travel on a premium ticket expect allowances up to 32 kg (70 lb). Leave a safety margin of 1–2 kg (2–4 lb) and 2–3 cm on dimensions to avoid unexpected surcharges.
Practical steps to get exact numbers: place the case on a flat surface; use a tape from the furthest outer points for length, then width across the broadest face, then height from base to tallest exterior point. Include wheels, external pockets and protruding handles in each measurement. For soft-sided cases compress fully and note the maximal bulge; for irregular items measure at multiple angles and record the largest values.
For weight use a handheld scale designed for travel or a bathroom scale: weigh yourself, then weigh yourself while holding the packed case and subtract to get the bag mass. If using a handheld hook scale suspend the packed case by its handle and read directly. Weigh after final packing and again after redistribution if you move items between the main case and carry-on. Keep an extra 1–2 kg buffer to account for scale variance and airport rounding.
Airline policies differ: always open the carrier’s published rules for external dimensions, allowed calculation method (linear sum versus per-side limits) and whether they count wheels/handles. Oversize fees commonly start around $75–$150 for domestic flights and $100–$300+ internationally; weight penalties often mirror those ranges. If the item exceeds linear limits but stays under weight you may still face an oversize fee–check both limits.
Packing tips to stay within limits: distribute heavy items into a personal item or backpack you will carry; use compression cubes or vacuum bags for soft gear; remove unnecessary accessories (removable wheels, strapped tripods) when possible; fasten loose straps and compress external pockets. Photograph the packed case next to a tape measure and a scale readout; keep these images and the carrier’s allowance on your phone to present at the counter in case of disputes.
Determine dimensions for airline hold baggage
Use a retractable tape to record external height, width and depth, including wheels and fixed handles; log values in both centimeters and inches and present them as H × W × D. For soft-sided cases, take readings with the main zipper closed; if the shell is expandable, take an additional set with that zipper extended if you plan to use the extra capacity.
Linear size limits and typical weight caps
Add H + W + D to obtain the linear dimension. Major international carriers set a 158 cm (62 in) linear cap for items transported in the aircraft hold; some domestic or low-cost airlines set limits between 140–158 cm. Weight limits commonly are 23 kg (50 lb) for standard economy and 32 kg (70 lb) for premium cabins; certain budget carriers use 20 kg as the standard. Oversize or overweight fees commonly range from roughly $50 to $300, with freight rates higher for very large pieces. Refer to your carrier’s published allowances and convert kg↔lb using 1 kg = 2.2046 lb when comparing rules.
Practical technique and packing tips
Place the case on a flat surface: measure the greatest vertical span (including feet), then the widest point, then the deepest point across wheels and protrusions. For weight, use a handheld digital luggage scale attached to the top handle, or weigh the loaded item on a bathroom scale and subtract the empty tare weight if known; zero the scale before the final reading for better accuracy. If detachable parts (removable wheels, add-on pockets) will travel detached, weigh both configurations and accept the one you will actually present at the airport. Position heavy items toward the center to avoid concentrated compression at conveyor points and redistribute excess kilos into a companion bag or cabin item to avoid surcharges. For cleaning small removable items before final weighing see how to clean dish scrubber.
Total external dimensions: length + width + height including wheels and protruding handles
Use a rigid tape and record the three external values with wheels and any protruding handles included; note both collapsed and fully extended handle totals and use the larger when submitting to a carrier.
- Place the case upright on a flat, hard surface with wheels touching the floor and all external pockets zipped and straps fastened.
- Length (L): take the longest external side from outermost seam or bumper to opposite outer edge, including corner guards.
- Width (W): take across the narrow side at the maximum external point, including side pockets, buckles and fixed handles.
- Height (H): take from the floor-contact point of the wheels up to the highest external item – this includes wheel housings, raised handles, ID tags and top bumpers.
- Telescopic handles: record H both with the handle retracted and with it fully extended; use the larger resulting L+W+H total. If the handle is removable, include it unless the carrier explicitly states otherwise – confirm the carrier’s rule before travel.
- External attachments: include wheels, fixed and removable handles, external straps, bottle pockets, name tags, and any permanently attached accessories. For soft-sided cases add a small allowance for fabric bulge (see next point).
- Unit conversion and rounding: sum L+W+H for the linear total. Typical limits to compare against: 158 cm = 62 in. Round each measurement up to the nearest whole centimetre or 1/8 inch before summing.
- Practical margin: add ~2 cm (0.8 in) to the linear total for soft cases and ~1 cm (0.4 in) for hard-shells to allow for compression and measurement variance.
Example
- Rigid case on wheels: L 75 cm, W 40 cm, H 30 cm (handle retracted) → linear = 145 cm.
- Same with handle extended +15 cm → extended linear = 160 cm; use 160 cm if carrier enforces extended-handle measurement and the limit is 158 cm.
Quick checklist
- Use a metal or rigid tape; avoid soft fabric tapes that sag.
- Take each dimension twice and photograph tape placement as evidence.
- Include all permanent external parts; exclude compressible internal contents but keep the buffer margin for fabric cases.
Weigh packed suitcase: handheld scale, bathroom scale, and reading tips for accuracy
Prefer a handheld hanging scale for a single-bag reading; pick a model rated ≥50 kg (110 lb) with 0.05–0.1 kg (50–100 g) resolution and an auto‑hold function.
Handheld procedure: attach the scale strap to the suitcase top handle (use a reinforced handle or a luggage strap under the handle if needed), lift vertically until the suitcase clears the floor, keep the scale at eye level to read the display, wait for the hold/stable symbol, then record the value. Avoid any swing – hold elbows close to the body and lift smoothly. If the scale offers unit selection, use kilograms for most airline limits (1 kg = 2.20462 lb).
Bathroom-scale procedure: place the digital scale on a flat, hard surface (tile, hardwood). Method A – weigh the empty scale to confirm zero, place the suitcase centered on the platform (wheels and handle may overhang; that’s acceptable) and read when the digits stabilize. Method B (more accurate for heavy or awkward suitcases) – step on alone and note your weight, then step on holding the suitcase and subtract: bag weight = (you + bag) − (you). Repeat both readings and average.
Accuracy tips: zero or tare the device before each use; swap batteries when screen dims; avoid carpet or uneven ground; perform readings at room temperature for consistent electronics. Take two consecutive readings and use the average; if the two differ by >0.2 kg, take a third and discard the outlier. Keep a 1.0 kg (2.2 lb) margin below the airline allowance to cover rounding rules and small scale errors.
Common pitfalls and fixes: swinging during handheld lifts → steady stance and slow lift; digital drift → powercycle and re-zero; low-capacity scale → use a higher-capacity model (handheld 50–60 kg or bathroom scale 150 kg+); forgotten outer-pocket items → zip all pockets and weigh again; mixed units → convert precisely (kg→lb multiply by 2.20462) and round in the same direction the carrier enforces (many carriers count fractions as whole units).
Final checklist before departure: verify battery level, confirm units, perform two averaged readings, leave a 1.0 kg buffer under the allowable weight, and redistribute heavy items between bags if any reading exceeds your target buffer.
Soft and expandable bags: account for compression, zippers and packed shape changes
Pack to travel-ready fullness, close the primary zipper, tighten external straps or press under a 10–15 kg weight for 30 seconds, then take external dimensions at the bag’s largest points; record both with the expansion zipper closed and opened, and use the larger figure for compliance with size limits.
Practical steps
1) Place the filled bag on a flat surface. Lay a straight edge (ruler, board) across the tallest bulge and measure from floor to straight edge with a cloth tape–this finds the true maximum height/depth rather than an averaged value.
2) For width and length, align the bag with a flat baseline and measure the farthest protrusions (handles, external pockets, shoe bulges). Include wheels and fixed hardware in these readings.
3) Test two states: main zipper closed (normal profile) and expansion zipper engaged. Expansion pools typically add 20–80 mm; note both numbers and plan on the larger.
Numeric allowances and packing tactics
Add 10–30 mm for fabric compression/tolerance and another 5–15 mm for seam and zipper bulge when reporting dimensions; leave a safety margin of 10–20 mm under any published limit to avoid disputes. Typical effects: internal compression straps can reduce depth by 10–60 mm depending on contents; bulky items (boots, toiletries) can create localized bulges of 30–100 mm–measure at the bulge and, if possible, reposition bulky items toward the center to shave external width.
Use packing cubes and compression sacs for textiles to lower profile by up to 40–60% of the garment thickness, and place rigid items along the spine to keep sidewalls flatter. If carrying fold-flat gear such as a compact stroller or umbrellas, stow them fully collapsed along one side–see best umbrella stroller that reclines flat and best ratwd umbrellas for compact options.
If the expansion zipper is used only occasionally, take a photo of the zipped-open profile as evidence; at gates staff may compress soft bags in a measuring frame, so keep measured dimensions consistently reproducible by packing in the same way each trip.
Compare dimensions and weight against airline rules and calculate potential excess fees
Immediately compare your item’s total linear size (L+W+H including wheels and external handles) and packed weight to the carrier’s published linear and weight allowances; if either exceeds the threshold, add base bag charges plus any overweight and oversize surcharges to get the expected airport cost.
Convert units before comparing: linear_cm = L_cm + W_cm + H_cm; linear_in = linear_cm / 2.54. weight_lb = weight_kg * 2.20462. Round up to the next whole kilogram or pound – most agents use rounded values when enforcing limits.
Determine applicable allowance by route/fare/class/club benefit. Then calculate overage: over_linear = max(0, linear_measured − allowed_linear). over_weight = max(0, weight_measured − allowed_weight). If your carrier uses brackets, match your over_weight to the bracket fee; if it charges per unit, excess_fee_weight = over_weight_units * unit_rate.
Illustrative examples (use only as a calculation template; actual carrier fees vary): Example A (typical domestic rule): allowance = 158 cm and 23 kg; base first-bag fee = $30; overweight 23–32 kg = $100; >32 kg = $200; oversize (>158 cm) = $150. For a case at 165 cm and 28 kg: fees = $30 (base) + $150 (oversize) + $100 (overweight) = $280. Example B (per-kg surcharge): allowance = 158 cm, 23 kg; base included; overweight rate = $12 per kg over. For a 27 kg item: over_weight = 4 kg → surcharge = 4 × $12 = $48; add oversize if linear limit exceeded.
Quick practical checks to lower fees: move heavy items into a carry piece or partner’s allotment; remove dense items (shoes, liquids) to personal carry; consolidate or split to stay under the nearest bracket (e.g., 23 kg → 22.9 kg avoids the overweight bracket); compare typical courier rates for shipping extra weight – sometimes a prepaid parcel is cheaper than combined airport surcharges.
