Industry Spotlight · Weighment
Shrinkage or Short Weight? Reading the Weighbridge Gap
Dispatch and receipt weights rarely match. Most of the argument that follows comes from not knowing which kind of difference you are looking at.
A consignment leaves at one weight and arrives at another. This is normal, expected, and the source of more disputes than almost anything else in the trade — because two entirely different things produce the same symptom. Some of the difference is the potatoes. Some of it is the measurement. Telling them apart is the whole skill.
Genuine loss is physical: moisture leaving the tuber, soil falling away, handling damage. It is real, it is unavoidable, and it is nobody’s fault. Measurement difference is procedural: different weighbridges, different tare assumptions, different calibration dates. It is also real, and it is entirely fixable.
Treating the second kind as if it were the first is how a trader absorbs a cost that was never his. Treating the first as if it were the second is how a working relationship gets damaged over something neither party controls.
Where the difference comes from
Moisture loss — genuine and unavoidable
Potatoes lose water continuously after lifting, and the rate rises with temperature, air movement and time. A consignment held before dispatch and then moved in warm conditions will weigh less on arrival than it did at loading. No process change eliminates this; it can only be reduced by shortening the interval and controlling the conditions.
Soil and adhering material
What was weighed at dispatch may have included soil that did not survive the journey. This is not shrinkage and it is not short weight — it is a difference in what was being weighed. Consignments dispatched shortly after lifting are the most affected.
Tare and bag weight assumptions
Gross weight minus an assumed tare gives net. If dispatch and receipt assume different bag weights, or count a different number of bags, the two nets will differ even when the potatoes are identical. This is arithmetic rather than physics, and it is the most common avoidable cause.
Different weighbridges, different readings
Two instruments, two calibration histories, two levels of maintenance. A weighbridge that has drifted produces a consistent difference on every consignment that crosses it — which is why a persistent gap with one particular destination is worth investigating as a measurement question, not a quality one.
How the vehicle was weighed
Whether the vehicle was weighed full then empty, whether the driver was aboard both times, whether fuel was added between weighings. Small procedural differences produce differences large enough to argue over.
What the gap costs
| Consignment | Gap observed | Value at ₹1,200/qtl |
|---|---|---|
| 100 quintals | 0.5 quintal | ₹600 |
| 100 quintals | 1.0 quintal | ₹1,200 |
| 100 quintals | 2.0 quintals | ₹2,400 |
| Across a 40-consignment season | 1.0 quintal each | ₹48,000 |
Illustrative arithmetic showing how a per-consignment gap scales across a season. The gap sizes are examples for calculation, not observed averages for any route or commodity.
A difference too small to argue about on one load becomes the largest uninvestigated cost of the season when it repeats on every load.
What to record, and when
Record the dispatch weight with its date, time and weighbridge. A weight without a source and a timestamp cannot be defended later, and defending it later is exactly when it matters.
Note the tare basis explicitly. Bag count and assumed bag weight, written down at dispatch. This single line removes the most common cause of an unexplained difference.
Photograph the loaded vehicle and the weighbridge slip. Two photographs at dispatch cost nothing and resolve most disputes before they become arguments.
Watch for patterns, not incidents. A one-off difference is probably shrinkage. The same difference every time, on the same route, is probably measurement — and that is worth raising.
Most of what prevents these disputes is discipline at dispatch rather than anything technological. The slip you kept, the tare you wrote down and the photograph you took are what settle an argument three weeks later, and no platform substitutes for any of them. What a marketplace can remove is the ambiguity that arrives before the load does — keeping the agreed quantity and condition in the listing rather than in somebody’s memory, which is the practical contribution Potato Bazaar makes here. The weighing itself remains between you, your weighbridge and your counterparty.
Connect Directly
List with quantities stated clearly
Specify what you are selling precisely, so both sides start from the same description.
The short version
Some of the gap is the potatoes and some of it is the measurement. Record the dispatch weight, its source and the tare basis, then look for patterns rather than incidents. A repeating difference on one route is a measurement question worth asking.
Why do dispatch and receipt weights differ?
Two separate causes produce the same symptom. Genuine physical loss — moisture leaving the tuber, soil falling away, handling damage — is unavoidable. Measurement differences from different tare assumptions, different weighbridges or different weighing procedures are avoidable, and distinguishing the two is the key to resolving disputes.
What is a normal amount of shrinkage?
It depends on the interval between lifting and weighing, the temperature and air movement in transit, and how the consignment was handled. There is no single figure that applies across routes and seasons, which is why the useful approach is to track your own consignments over time and look for deviations from your own pattern.
How do I tell shrinkage from a measurement problem?
Look for repetition. Genuine shrinkage varies with conditions and will differ between consignments. A measurement problem — a drifted weighbridge or an inconsistent tare assumption — produces a similar difference every time on the same route, which is the signature worth investigating.
What should I record at dispatch?
The gross weight with the date, time and weighbridge identity; the bag count and assumed bag weight used to reach the net; and photographs of the loaded vehicle and the weighbridge slip. This takes a few minutes and resolves most later disagreements immediately.
Who bears the cost of a weight difference?
That depends entirely on what was agreed beforehand, which in practice is usually nothing. Agreeing in advance how a difference beyond a stated threshold will be treated is far easier than negotiating it after a consignment has arrived and one party is already out of pocket.
Editorial disclosure: This is an Industry Spotlight published in partnership with Potato Bazaar (S.K. Agri Exports Private Limited). The editorial framing, research and references are the responsibility of the IndianPotato.com editorial team. The value table is illustrative arithmetic demonstrating how a per-consignment gap scales; the gap sizes are examples for calculation and not observed averages. Potato Bazaar does not weigh, inspect or verify consignments, and nothing here should be read as suggesting otherwise.
