Volumetric Weight Calculator
Compute volumetric weight: (L × W × H cm) / factor (5000 air, 6000 ground). Compare to actual weight.
Volumetric (dimensional) weight
Volumetric weight — also called dimensional weight or "peso pena" in Brazilian freight slang — is the freight cost a carrier charges for bulky-but-light packages. Formula: vol_weight (kg) = (L · W · H in cm) / divisor. The carrier then charges the greater of actual weight and volumetric weight. Standard divisors: 5000 (IATA international air freight, also adopted by Correios SEDEX and most domestic air carriers), 6000 (road freight in Brazil, ANTT reference), and 4000 (express/courier such as FedEx, DHL and UPS for premium services). Example: a 40×30×20 cm box uses 24,000 cm³; at divisor 5000 the volumetric weight is 4.8 kg. If the actual weight is 3 kg, billing uses 4.8 kg. This pricing protects carriers from low-density cargo that takes up trailer/aircraft space disproportionate to its mass.
Applications and context
Used by e-commerce operators (Mercado Livre, Shopee, Amazon FBA), 3PL warehouses, and freight quote engines (Frete Click, Melhor Envio, Kangu). Reducing package dimensions through proper boxing is often cheaper than reducing weight.
FAQ
Why are divisors different? They reflect density assumptions per modal: aircraft cargo holds penalise volume more than road trucks, so air uses 5000 and road 6000.
Does Correios use this? Yes — SEDEX and PAC apply volumetric weight with divisor 6000 for packages above 5 cm in any dimension.
How to reduce volumetric weight? Eliminate empty space, use vacuum packing for textiles, and prefer custom-fit boxes over oversized ones.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.