Transit estimator: door-to-door days from our own parcel records

Ask when it lands, and get an answer built from parcels rather than from a promise. The estimator takes the day counts we recorded on one line into one destination, finds the middle value, applies the seasonal factor if you are in the peak window, then adds your warehouse days and the last mile. Six records give a median; fewer than three give a range and a sentence saying why.

Five inputs shape the answer. The ship date anchors the calendar and opens at today, because every other figure is counted forward from the day the parcel leaves. The sample field takes the recorded door-to-door day counts for your line, comma separated, and everything else is derived from them. Warehouse days is the gap between submitting a parcel and the line collecting it — yours to control, so it stays a separate field rather than being buried in the median. The peak flag multiplies every figure by 1.25 and is set automatically between October and December. Last-mile days defaults to 3, the delivery leg after the parcel clears the port.

The default samples are six GD-EUB parcels delivered between 2026-08-01 and 2026-09-30, the window this site records in: 9, 11, 12, 12, 14 and 16 days. They are kept on screen because six records sit comfortably above the three-record floor while still showing a real spread. Change one number and watch both the median and the spread move — a single 30-day outlier would stretch the high figure without touching the middle, which is exactly why the median is the number we quote.

Read the middle, then read the edges. With an even count the median is the mean of the two middle values, so six records produce 12 days; the fastest and slowest records become the low and high figures. The peak flag multiplies all three by 1.25 before rounding to whole days, so an 11-day median becomes 14 and a 15-day slowest record becomes 19. Your warehouse days and the last mile are added afterwards, which is why the door-to-door total always exceeds the trunk figure by a fixed amount.

The three cases show the estimator in its three modes. Six records give a 12-day median and a 20-day door-to-door figure, with the spread running 17 to 24 days — plan around 20 and keep a week in reserve. Five records in the peak window give 14 days and 21 days door to door, with the spread pushing to 26. Two records give no median at all: only 12 to 21 days and a note explaining that we do not publish a middle value below three records.

Use the spread rather than the median when a date matters. A parcel needed for a specific weekend should be judged against the high figure, not the middle one: on the default records that is 24 days, not 20. If the high figure misses your date, either ship earlier, choose a faster line, or accept that the parcel may arrive after the event. Nothing in this tool can compress the trunk leg, and the last mile runs on the carrier timetable rather than on yours.

Three further cautions belong on the record. Parcels still moving are excluded, so the median describes completed journeys only. A parcel held at customs is reported as in transit and never folded into the median, which means the figures here are transit time rather than a delivery promise. And the 1.25 peak factor is a rule this site applies to its own records rather than a published service guarantee — switch it off if you want the raw spread.

Compare the estimate against the shipping bands page before you choose a line. A faster line usually sits in a higher band, and the difference between the band fees is the price of the days you are choosing between. When two lines are within a few pounds and their spreads overlap, take the cheaper one and put the difference into the declared value instead; when one spread ends before the other begins, you are paying for certainty rather than speed, and that is worth pricing properly.