Calculate cubic metres (CBM) for a shipment from per-piece dimensions. CBM is the standard volume unit in international shipping: 1 CBM = 1m x 1m x 1m = 1,000 litres, and ocean freight prices per "freight tonne" (1 CBM or 1,000 kg, whichever is greater).
Behavior: deterministic — identical inputs always return identical figures; total volume = pieces x per-piece CBM, with conversions to cubic feet, cubic inches and litres included. Missing or non-positive dimensions error with a validation message naming the parameter. Rate-limited (anonymous use: 25 requests/day per IP): a 429 error body carries retry_after_seconds and a Retry-After header — back off and retry, or call get_subscribe_link for higher limits.
Returns: cbm_per_piece, total_cbm, cubic_feet, litres, cubic_inches and pieces under result, plus confidence, _source and citation (the FreightUtils v1 response envelope).
Related: chargeable_weight_calculator (air billing weight from the same dims), consignment_calculator (multi-line totals), unit_converter (single conversions), shipment_summary (full composite analysis).