What this calculator does
Shipping cost per unit is the average cost of shipping to move one unit, worked out from total shipping spend over a period divided by how many units were shipped in that same period. It turns a lump-sum freight or courier bill into a per-unit figure that can be built into pricing and margin decisions.
This is an average across everything shipped in the period, so it blends together different destinations, package sizes and carriers into a single number. That is useful for high-level pricing and margin work, but it will not match the actual cost of shipping any one specific order, which depends on its own weight, size and destination.
The formula
Divide total shipping cost by the number of units shipped over the same period. The result is the average shipping cost carried by each unit sold.
| Term | Meaning |
|---|---|
| Cost per unit | The average shipping cost per unit: total shipping cost ÷ units shipped. |
| Total shipping cost | All freight, courier and postage costs paid over the period being measured. |
| Units shipped | The total number of individual units shipped in that same period. |
The inputs explained
| Field | What to enter |
|---|---|
| Total shipping cost ($) | The total amount spent on shipping over the period, including freight, courier and postage costs. |
| Units shipped | The total number of units shipped over that same period. |
When to use it
Building shipping into product pricing
A per-unit shipping cost is a straightforward figure to fold into the cost base used when setting a retail price, alongside the product’s own cost of goods.
Comparing carriers or shipping methods
Running the same total volume through different carriers or service levels and comparing the resulting cost per unit shows which is cheapest on average for the mix of orders actually being shipped.
Tracking shipping cost inflation
A rising cost per unit over successive periods, even with steady order volumes, points to carrier rate increases or a shift toward more expensive shipping methods worth investigating.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How cost per unit changes as total shipping spend increases at a fixed unit count
A fixed 600 units shipped, across a range of total shipping spend.
| Total shipping cost | Shipping cost per unit |
|---|---|
| $600 | $1.00 |
| $1,200 | $2.00 |
| $1,800 | $3.00 |
| $2,400 | $4.00 |
| $3,600 | $6.00 |
| $4,800 | $8.00 |
How cost per unit changes as units shipped increases at a fixed shipping spend
A fixed $1,800 shipping spend, spread across a range of unit volumes.
Questions
Should this figure include packaging materials as well as freight?
That is a choice to make consistently: whichever costs are included in the total shipping cost figure, keep the same scope every time it is calculated, so comparisons over time and against other periods stay meaningful.
Why is my actual cost to ship a single order different from this average?
This figure is a blended average across every order in the period, mixing different weights, sizes and destinations together. Any individual order will usually cost more or less than the average, depending on how it compares to the typical shipment in that mix.
How should this feed into free-shipping decisions?
Knowing the average shipping cost per unit is a starting point for deciding whether to absorb shipping into the product price, offer free shipping above a threshold, or charge it separately, since each approach affects margin differently.
Does a falling cost per unit always mean shipping got cheaper?
Not necessarily. It can also reflect a shift toward larger orders with more units each, spreading the same per-order freight cost over more units, rather than any change in the underlying shipping rates.
To see how shipping and other variable costs affect the point at which a product turns profitable, use the e-commerce break-even calculator.