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ShipMargin

Glossary

The terms that turn up on shipping invoices and fee schedules, defined in plain language and linked to the calculator that uses each one.

ACOS Advertising cost of sale
Ad spend divided by the revenue those ads produced. Your console reports it; only your fee stack can tell you what level of it you can afford. Calculator →
Aged inventory surcharge
A per-unit fee Amazon charges once stock has sat in the network past a threshold, reaching $0.30 at twelve months and $0.35 beyond fifteen. Calculator →
Billable weight
Another name for chargeable weight — the figure the carrier actually multiplies by your rate. Calculator →
CBM Cubic metre
The volume unit freight is quoted in. Length times width times height in metres, or centimetres cubed divided by a million. Calculator →
Chargeable weight
The greater of actual and volumetric weight, rounded up to the carrier's billing increment. Calculator →
CIF Cost, insurance and freight
A valuation basis where the customs value includes freight and insurance, so your shipping cost is taxed too. Used by most countries. Also an Incoterm. Calculator →
DAP Delivered at place
The seller delivers to the buyer's address but the buyer owes duty and import tax. This is why a customer gets a courier invoice after the parcel arrives. Calculator →
DDP Delivered duty paid
The seller pays everything including duty and import tax. The only Incoterm that gives a consumer a genuinely final checkout price. Calculator →
De minimis
The value below which a country waives duty, tax or both. The US suspended its $800 threshold in August 2025; India, Nigeria and Brazil have never had one. Calculator →
Dim divisor
The number you divide cubic volume by to get billable weight. 139 for inches and pounds, 5000 for centimetres and kilograms, on most express carriers. Calculator →
Dimensional weight
Billable weight derived from a parcel's size rather than its mass, because a vehicle runs out of space before it runs out of payload. Calculator →
EOQ Economic order quantity
The order size where the cost of ordering more often exactly equals the cost of holding more stock. Calculator →
FOB Free on board
A valuation basis and Incoterm where the seller delivers on board at origin. As a customs basis it excludes freight, which is how the US assesses duty. Calculator →
Freight class
The NMFC classification that prices US LTL freight, derived mainly from density in pounds per cubic foot, on a 13-tier scale since July 2025. Calculator →
Fuel surcharge
A percentage added to the base rate, recalculated weekly against a published fuel index. Never a fixed number, which is why hardcoding it goes stale within days. Calculator →
Girth
Twice the width plus twice the height, using the two shorter sides. Combined length and girth is what postal operators cap. Calculator →
HS code Harmonised System code
The international commodity classification that determines your duty rate. Six digits are global; countries extend to eight or ten. Calculator →
IOSS Import One-Stop Shop
The EU scheme letting sellers collect VAT at checkout on consignments up to €150 rather than having it collected on delivery. Calculator →
Landed cost
Everything it takes to get one unit from the supplier's door to your shelf: goods, freight, insurance, duty, non-reclaimable tax, clearance and inland delivery. Calculator →
LCL Less than container load
Shared ocean freight, quoted per revenue tonne — whichever is greater of one cubic metre or 1,000 kg. Calculator →
LTL Less than truckload
Shared road freight, priced in the US on NMFC freight class rather than a volumetric divisor. Calculator →
Referral fee
The marketplace's commission, charged on the total the buyer pays including postage — not on the item price alone. Calculator →
Reorder point
The stock level that triggers a purchase order: lead-time demand plus safety stock. Calculator →
Revenue tonne
The LCL billing unit: whichever is greater of one cubic metre or one metric tonne. Calculator →
ROAS Return on ad spend
Revenue divided by ad spend. The reciprocal of ACOS: 25% ACOS is 4× ROAS. Calculator →
Safety stock
Buffer inventory sized against the variability of demand and lead time at a chosen service level — not against average demand. Calculator →
TACOS Total advertising cost of sale
All ad spend against all revenue, organic included. A falling TACOS with rising revenue means organic rank is taking the load. Calculator →
Ti-Hi
Cartons per layer (Ti) and number of layers (Hi). Multiply for cartons per pallet. Calculator →
Volumetric weight
The same calculation as dimensional weight, under the term used outside the United States, usually implying centimetres and kilograms. Calculator →