Dimensional Weight API
Shipping dimensional-weight maths as an API. Carriers bill the greater of a parcel's actual weight and its dimensional (volumetric) weight — the volume divided by a carrier "dim divisor" — so a big, light box can cost far more than the scales suggest. The dimweight endpoint computes the dimensional weight in both pounds and kilograms from the length, width and height (in inches or centimetres) and a dim divisor, which you can give directly or pick by carrier (UPS, FedEx, USPS, DHL, IATA). The billable endpoint takes the actual weight as well and returns the billable weight — the greater of actual and dimensional — telling you which one you will be charged on. The girth endpoint computes the girth (twice the width plus height of the two smaller sides), the length-plus-girth and the longest side, and flags whether the parcel is oversize against length limits (defaulting to typical US ground values). Everything is computed locally and deterministically, so it is instant and private. Ideal for e-commerce checkout and shipping estimators, fulfilment and warehouse tools, freight and logistics software, and packaging optimisation. Pure local computation — no key, no third-party service, instant. Live, nothing stored. Divisors and limits are typical published values — confirm with your carrier and service. 3 endpoints. This is dimensional-weight maths; for live shipping rates use a carrier's own API, and for plain unit conversion use a unit-conversion API.
api.oanor.com/dimweight-api
