Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
139 for most US carriers
Result
Shipping cost per order
$18.12
Billable weight (lb)
8.06
Dimensional weight (lb)
8.06
How it is billed
Billed on dimensional weight
Free-shipping threshold to stay level
$40.27
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter box length (in).
- 2Enter box width (in).
- 3Enter box height (in).
- 4Enter actual weight (lb).
- 5Enter dimensional divisor — 139 for most US carriers.
- 6Enter rate per billable pound ($).
- 7Enter packaging cost ($).
- 8Enter gross margin on the order (%).
- 9Read your shipping cost per order on the right — it updates as you type.
- 10Hit Share to keep the scenario or send it to someone.
About this calculator
Carriers bill on whichever is greater: actual weight or dimensional weight. Bulky, light items get charged on volume, which is why oversized boxes quietly destroy margin.
Worked example
Using the values the calculator loads with:
Inputs
- Box length: 14 in
- Box width: 10 in
- Box height: 8 in
- Actual weight: 3 lb
- Dimensional divisor: 139
- Rate per billable pound: 2.1 $
- Packaging cost: 1.2 $
- Gross margin on the order: 45 %
Results
- Shipping cost per order: $18.12
- Billable weight (lb): 8.06
- Dimensional weight (lb): 8.06
- How it is billed: Billed on dimensional weight
- Free-shipping threshold to stay level: $40.27
What each field means
Inputs
- Box length (in)
- The box length used in the calculation, measured in in. Starts at 14 in so you have a working example on load.
- Box width (in)
- The box width used in the calculation, measured in in. Starts at 10 in so you have a working example on load.
- Box height (in)
- The box height used in the calculation, measured in in. Starts at 8 in so you have a working example on load.
- Actual weight (lb)
- The actual weight used in the calculation, measured in lb. Starts at 3 lb so you have a working example on load.
- Dimensional divisor
- 139 for most US carriers
- Rate per billable pound ($)
- The rate per billable pound used in the calculation, measured in $. Starts at 2.1 $ so you have a working example on load.
- Packaging cost ($)
- The packaging cost used in the calculation, measured in $. Starts at 1.2 $ so you have a working example on load.
- Gross margin on the order (%)
- The gross margin on the order used in the calculation, measured in %. Starts at 45 % so you have a working example on load. Accepted range: 1–100 %.
Results
- Shipping cost per order
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Billable weight (lb)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Dimensional weight (lb)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- How it is billed
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Free-shipping threshold to stay level
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the shipping cost calculator work?
Carriers bill on whichever is greater: actual weight or dimensional weight. Bulky, light items get charged on volume, which is why oversized boxes quietly destroy margin. The underlying maths is: Dimensional weight = L × W × H ÷ Divisor. Billable weight = max(actual, dimensional).
What do I need to enter?
8 values: box length, box width, box height, actual weight, dimensional divisor, rate per billable pound, packaging cost, and gross margin on the order. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the shipping cost per order result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Shipping Cost Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/shipping-cost
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/shipping-cost" target="_blank" rel="noopener">Shipping Cost Calculator — RevenueLab</a> (2026).</p>
Source: [Shipping Cost Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/shipping-cost) (2026).