Calculate CBM in Inches
Free inches to CBM calculator for shipping, freight and cargo. Convert L × W × H in inches to cubic meters in seconds.
The fastest way to calculate CBM in inches is with our free online CBM calculator. Enter length, width and height in inches, set quantity and weight, and we instantly convert the result to cubic meters (m³), cubic feet (ft³), volumetric weight and container fit — including 20ft, 40ft and 40HC.
Need mixed carton sizes, weight and container fit? Use the full CBM Calculator.
Inches to CBM formula
CBM = (Length × Width × Height in inches) ÷ 61,023.74 × Quantity. Or convert each side to meters first by dividing by 39.37, then multiply L × W × H × Qty. Both methods give the same answer; the divisor 61,023.74 is simply 39.37³.
Example 1 — Standard US export carton
- Carton: 24 × 18 × 12 inches
- Volume per carton = 24 × 18 × 12 ÷ 61,023.74 ≈ 0.0849 CBM
- 50 cartons → 0.0849 × 50 ≈ 4.25 m³
- Equivalent CFT ≈ 150 ft³
Example 2 — Large furniture carton
- Box: 48 × 30 × 24 inches
- Volume per box = 48 × 30 × 24 ÷ 61,023.74 ≈ 0.5663 CBM
- 20 boxes → 11.33 m³ — comfortable LCL
- 40 boxes → 22.65 m³ — close to a 20ft FCL (see 20ft specs)
Why calculate CBM in inches?
Most US, UK and many Asian factories quote carton dimensions in inches. A reliable inches to CBM calculator avoids manual conversion errors that lead to wrong freight quotes, overbooked containers and invoice disputes with shipping lines and customs brokers.
Use cases for an inches-to-CBM calculation
- Ocean LCL and FCL bookings priced per CBM
- Air freight volumetric weight (divisor 6000 cm³/kg)
- Courier shipments via DHL, FedEx and UPS (divisor 139 in³/lb)
- Warehouse 3PL storage billed per cubic meter or pallet
- Amazon FBA inbound shipment size planning
Inches to CBM quick conversion table
- 12 × 12 × 12 in → 0.028 CBM (1 ft³)
- 18 × 12 × 12 in → 0.042 CBM
- 24 × 18 × 12 in → 0.085 CBM
- 30 × 20 × 18 in → 0.177 CBM
- 48 × 40 × 36 in → 1.133 CBM (one full pallet stack)
US & FBA export carton reference (inches)
- Amazon FBA small standard — 15 × 12 × 8 in → 0.0236 CBM
- Amazon FBA large standard — 18 × 14 × 8 in → 0.0330 CBM
- FBA oversize small — 24 × 18 × 12 in → 0.0849 CBM
- US master shipper carton — 20 × 16 × 14 in → 0.0734 CBM
- Costco club-pack case — 24 × 16 × 14 in → 0.0881 CBM
- Home Depot bulky item box — 36 × 24 × 18 in → 0.2548 CBM
Worked example — US furniture exporter (Los Angeles → Rotterdam)
- Step 1 — Coffee table cartons: 48 × 30 × 10 in → 14,400 in³ ÷ 61,023.74 = 0.236 CBM each.
- Step 2 — Order of 60 cartons → 60 × 0.236 = 14.16 CBM.
- Step 3 — Palletize on 48 × 40 in pallets, 4 cartons per pallet, 15 pallets total.
- Step 4 — Pallet footprint 48 × 40 × 40 in (with cargo) → 0.629 CBM per pallet × 15 = 9.43 CBM billable (LCL charges pallet cube, not carton cube).
- Step 5 — Compare LCL revenue tons (max of 14.16 CBM vs 3.6 t) → 14.16 W/M is the invoice quantity.
FAQs — CBM in inches
Where does the divisor 61,023.74 come from?
1 meter = 39.3701 inches, so 1 m³ = 39.3701³ ≈ 61,023.744 in³. Dividing cubic inches by that constant converts directly to cubic meters.
Do US customs use inches or centimeters for CBM?
US CBP accepts both, but the international ocean bill of lading and forwarders' rate cards use CBM (metric). Convert inches to CBM before quoting — never leave dimensions in inches on the booking.
Is chargeable weight for FedEx/UPS ground the same as for their air service?
No. US domestic ground uses divisor 139 in³/lb; international express uses 139 as well but requires actual CBM on the AWB. Always check the account-specific rate card because contract shippers often get a higher divisor (166 or 194).
Open the free online CBM calculator to start measuring in inches, or read how to measure CBM, CBM in cm and CBM in feet.