Convert freight and logistics units: weight (kg, lbs, oz, tonnes, short_tons, long_tons), volume (cbm, cuft, cuin, litres, gal_us, gal_uk), length (cm, inches, m, feet, mm), plus two freight-specific targets valid only FROM cbm — chargeable_kg (air volumetric weight at the IATA 6,000 divisor, 1 CBM = 166.67 kg) and freight_tonnes (sea W/M, 1 CBM = 1 freight tonne).
Behavior: deterministic; the response names both units and states the formula used. Cross-dimension conversions (e.g. kg to litres) and freight targets from a non-cbm source error with the accepted-unit list. Note: short ton (US) = 2,000 lb, long ton (UK) = 2,240 lb, metric tonne = 2,204.6 lb. 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: input {value, unit, name}, result {value, unit, name}, formula and note under result, plus confidence, _source and citation (the FreightUtils v1 response envelope).
Related: cbm_calculator (dimensions to volume first), chargeable_weight_calculator (proper air billing weight with pieces and a custom divisor).