DIM Weight Calculator — UPS, FedEx, DHL & Canada Post

Accurate billable weight with correct rounding rules. Fast, free, no signup.

Box dimensions diagram: Length, Width, Height
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Package Dimensions
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How DIM Weight Works

1

Dimensional Weight

Carriers calculate a 'DIM weight' based on package size, not just actual weight.

2

DIM Divisors

UPS/FedEx use 139 (in³/lb). DHL uses 5000 (cm³/kg). Canada Post uses 5000 or 6000 depending on service.

3

Billable Weight

You pay for whichever is greater: actual weight or DIM weight.

Why Dimensional Weight Matters for Your Business

If you ship products regularly, understanding Dimensional Weight (DIM Weight) is crucial to maintaining your profit margins. Carriers like UPS, FedEx, DHL, and Canada Post don't just charge based on how heavy a package is; they also charge based on how much space it takes up in their delivery trucks and planes.

This means that if you ship a lightweight item in a large box, you might be billed for a much heavier weight than what the scale shows. Our free DIM Weight Calculator helps you determine the exact billable weight before you buy a shipping label.

How Do Carriers Calculate DIM Weight?

The general formula involves multiplying the length, width, and height of your package to find its cubic volume, and then dividing that number by a specific 'DIM divisor'. The divisor varies by carrier and by the unit of measurement used (inches vs. centimeters).

Stop Overpaying for Shipping

By using right-sized packaging and knowing your exact DIM weight, you can optimize your shipping strategy and avoid unexpected carrier adjustments. Explore our guides below to learn more about packaging strategies and cost reduction.

Frequently Asked Questions

Dimensional weight (DIM weight) is a pricing technique used by carriers. It calculates a theoretical weight based on package volume, ensuring large but light packages are charged fairly.

Multiply Length × Width × Height, then divide by the carrier's DIM divisor (139 for UPS/FedEx in inches, 5000 for DHL in centimeters).

If your package is large relative to its weight, the DIM weight exceeds actual weight. Carriers charge the higher of the two.

This calculator uses standard 2025 rules for general guidance. Actual rates may vary by service, account, and destination. Always verify with official carrier tools.

Yes! UPS/FedEx round each dimension up to the next inch. DHL uses standard rounding to centimeters, then rounds billable weight to the nearest 0.5 kg.

Canada Post uses 'Volumetric Equivalent' (VE). Priority/Xpresspost/Expedited services use divisor 5000. Regular Parcel uses 6000. Weight is rounded up to nearest 0.5 kg with a 0.75 kg minimum tier for most services.

Embed Widget

Add this calculator to your website with a simple iframe.

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