Merge or split calculator
Merging saves the base cost per parcel but can push a shipment over a line weight limit or into a worse volumetric bracket. This instrument shows both outcomes side by side.
Items and rates
One parcel versus two
| Option | Actual | Volumetric | Billed | Freight | Within limit |
|---|---|---|---|---|---|
| One parcel | 2.90 kg | 4.80 kg | 4.80 kg | $55.20 | Yes |
| Parcel 1 (2 items) | 2.30 kg | 3.20 kg | 3.20 kg | $40.80 | Yes |
| Parcel 2 (1 item) | 0.60 kg | 1.60 kg | 1.60 kg | $26.40 | Yes |
| Two-parcel total | $67.20 |
Difference (two parcels minus one)
+$12.00Merging is cheaper by $12.00.
One parcel pays the base cost of $12.00 once; two parcels pay it twice. That is what merging is buying, and crossing the line limit is what can take it away.
Parameters and when they were checked
| Parameter | Default | Range | Basis | Checked |
|---|---|---|---|---|
| Item A weight | 1.4 kg | 0–30 | Scale weight of the first item as recorded at the warehouse. | 2026-W40 |
| Item B weight | 0.9 kg | 0–30 | Scale weight of the second item. | 2026-W40 |
| Item C weight | 0.6 kg | 0–30 | Scale weight of the third item. | 2026-W40 |
| Line weight limit | 10 kg | 1–50 | The maximum billable weight the chosen line accepts in one parcel. | 2026-W40 |
| Rate per kg | 9 USD/kg | 1–60 | Your own quote per kilogram. | 2026-W40 |
| Base cost per parcel | 12 USD | 0–200 | Charged once per parcel, which is why merging usually wins on cost. | 2026-W40 |
- Source:
- Defaults are our starting figures; every one of them is editable on this page.
- Sample:
- Parameter rows carry no sample count of their own. Where a row depends on data, the sample is stated on the page that publishes it.
- Recorded:
- 2026-W40
- Known gap:
- These defaults are planning figures. Your own quote or invoice is the authority.
How to read the result
- One parcel pays the base cost once. Two parcels pay it twice, which is the cost merging is trying to avoid.
- A split can still win when the merged weight crosses the line limit, because an over-limit parcel may have to move to a more expensive line.
- The difference line tells you which way the arithmetic points. If splitting costs more, the page says so plainly.
- This instrument compares weight and cost only. It does not model customs treatment of a larger declared value, which is covered on the landed-cost page.
Using it
- Open the instrument above. It calculates with the defaults immediately, so there is nothing to set up before you see a result.
- Replace the defaults with your own figures. Each field names what it expects and which week its default was checked.
- Read the result panel. If a field falls outside its expected range, the page says so and pauses the calculation rather than returning a figure built on bad input.
- Use Reset to return every field to its default. Nothing you type is sent anywhere or stored after you leave the page, except the QC checklist, which stays in your browser.
Questions that come up
Is merging always cheaper?
No. It is cheaper until the merged parcel crosses a weight limit or a volumetric bracket that changes the rate. Below that point merging wins on base cost alone.
What if one item is heavier than the limit on its own?
Then it cannot ship in that line at all, and the page flags it. Splitting does not fix an item that exceeds the limit by itself.