Shipping window calendar
Dispatch and transit do not move smoothly through the year. Five windows account for most of the disruption, and each one has a different correct response: order early, consolidate early, or simply avoid.
Rows labelled structural are calendar facts that repeat every year. Rows labelled observed carry a week and a sample count. Where we have no observation, the page says so rather than estimating one.
Your plan
Where your week falls
ISO week 40 falls inside October Golden Week. Dispatch conditions are disrupted during this window.
11.11 campaign
Early-to-mid November. Seller dispatch slows for roughly two weeks around the campaign.
12.12 campaign
Mid-December. A shorter campaign window than 11.11, with a similar dispatch pattern.
Spring Festival
Late January to mid-February, dates move each year with the lunar calendar. Sellers stop shipping and warehouses run reduced hours for roughly three weeks.
October Golden Week
First week of October. A one-week national holiday; dispatch resumes the following week.
Late-November peak
Last week of November. Outbound line capacity tightens as global parcel volume peaks, so transit stretches even when dispatch is normal.
- Source:
- Lunar calendar dates and the published holiday schedule.
- Sample:
- No qualifying observation for any window at this time.
- Recorded:
- 2026-W40.
- Known gap:
- Spring Festival dates are confirmed for 2026: 2026-02-17, 2027: 2027-02-06, 2028: 2028-01-26. Later years are not yet confirmed and are not shown.
Parameters and when they were checked
| Parameter | Default | Range | Basis | Checked |
|---|---|---|---|---|
| Planned order week | 40 ISO week of 2026 | 1–52 | The week you expect to place the order. Used to place you on the calendar. | 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
- Each window lists three windows: when to order, when to consolidate and ship, and which weeks to avoid if the parcel is time-sensitive.
- Structural entries describe the holiday calendar and the dispatch pattern that follows it. They are the same every year.
- Observed entries describe something we recorded, with the week and the sample count attached. We currently hold no qualifying observation for these windows, so none is shown.
- Warehouse storage limits interact with these windows: a long holiday can eat into free storage days if items arrive just before it.
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
What is the single worst week to ship?
The week before Spring Festival. Sellers stop dispatching, warehouse hours shrink, and outbound capacity is already committed. If a parcel can move earlier, move it earlier.
Do campaigns slow international transit?
Not directly. Campaigns slow seller dispatch and warehouse intake. Transit slows later, when outbound volume peaks in late November.
Why show structural rows with no observed data?
Because the holiday calendar is verifiable and repeatable, while a single observation is not evidence of a pattern. Labelling them separately keeps both honest.