Fixed bins or random storage: what it means for the count

How goods are assigned to a place in the warehouse determines how they can be counted. With fixed-bin storage every item has its place; with random storage goods go wherever there is a free bin at the time. Both are legitimate, and both have consequences for the stock count. The decisive difference: in one case the item leads to the bin, in the other the bin leads to the item. Anyone who overlooks this will plan too little time for the count.

Fixed-bin storage: the item has its home

Every item has a fixed place, the count sheets are short and follow the range. If an item is missing, the empty bin is noticed at once. New staff find the goods quickly, and the count team can navigate by item number.

The drawbacks are the larger floor space needed, because places stay reserved even for slow-moving goods, and the overflow: if a delivery does not fit into the fixed bin, the rest stands somewhere else, and that is exactly where counting errors arise.

Random storage: the bin has its contents

The floor space is used better because any free bin can be filled. In return the same item stands in several bins, and without a reliable bin system the count turns into a search. The following applies:

• Every bin has an unambiguous number, visible on the rack.
• Every put-away, pick and transfer is posted to the exact bin.
• Counting goes from the bin to the item: bin by bin, with item number and quantity.
• The total quantity of an item is the sum over all its bins and only emerges in the analysis.

A calculation example (fictional)

A warehouse holds 900 items. With fixed-bin storage 900 bins plus 60 overflow bins are enough, so 960 count lines. With random storage the items stand on average in 2.5 bins, which gives 900 × 2.5 = 2,250 count lines. At the same pace of 40 lines an hour, the first count takes 960 ÷ 40 = 24 team hours in the first case and 2,250 ÷ 40 = about 56 team hours in the second. In practice, search time is added in the random warehouse. That does not mean random storage is worse. It moves the effort from floor space to system discipline, and that discipline must visibly work on count day.

What a reliable bin system needs

• Unambiguous, gap-free bin numbers that agree on the rack and in the system.
• Posting to the exact bin on every movement, including transfers within the warehouse.
• A rule for empty bins: they are reported and confirmed as "empty" during the count.
• A register of all bins, which serves as the basis for the gap control.
• Regular bin checks, not only before the stock count.

With mixed forms, such as fixed bins for fast-moving goods and random storage for the rest, the instructions must describe both areas separately. Overflow areas belong here too: they are the most frequent source of goods that appear on no list.

Counting method for each storage type

With fixed-bin storage, the item is looked for and its bin is counted; empty fixed bins are confirmed with zero. With random storage the team counts bin by bin, blind and in the order of the bin numbers, and the gap control checks that every bin appears on exactly one sheet. Counted zones are visibly marked. Movements in a zone during the count should be avoided or recorded separately, otherwise goods jump between two bins and are counted twice or not at all.

In short

Fixed bins or random storage: both can be counted cleanly if the bin system is right. In a warehouse audit, AuditMaster examines the bin system and, on request, labels racks and bins with barcodes as the basis for every later count.