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WeightVerified formula

USPS Dimensional Weight Calculator

Determine whether a US package is billed by actual or USPS dimensional weight.

Free · no sign-upRule: usps-dim-2026.07-v1
Package inputs
Use outside package dimensions. Your result stays on this device unless you choose to save it.
Priority Mail — Commercial
Live result Deterministic
Shipping intelligence
No AI estimates. Every output comes from the published formula.

Your result will appear here

Enter package data and calculate. No account is required.

How to use this tool

A decision, not just an output

Apply the current verified USPS Priority Mail commercial DIM rule. Read the output alongside its interpretation, assumptions, limitations, and source. Marketplace rates and external requirements should always be confirmed at the linked official source.

Formula & example

Transparent method

Dimensional weight = rounded package volume ÷ verified divisor; billable weight is the greater of actual and dimensional weight.

Example: A rectangular 18 × 14 × 10 in parcel exceeds one cubic foot and is divided by 139 after USPS dimension rounding.

Assumptions

  • • US domestic Priority Mail commercial rules and Zones 1–9.
  • • Measurements are rounded up to whole inches.

Limitations

  • • This does not calculate postage or contract rates.
  • • Other mail classes can have distinct eligibility rules.

Frequently asked questions

Is the USPS Dimensional Weight Calculator free?

Yes. The primary result is available without creating an account or entering an email address.

How is the result calculated?

Dimensional weight = rounded package volume ÷ verified divisor; billable weight is the greater of actual and dimensional weight.

What should I verify before using it?

This does not calculate postage or contract rates. Other mail classes can have distinct eligibility rules.

Are my inputs private?

Core inputs are processed in your browser. GetShipMargin Tools records anonymous interaction events, not the business values entered into this form.