Warehouse Operations — 4 calculators

Two orientation calculations. We try both box orientations (length along pallet length vs length along pallet width) and pick the one that fits more boxes per layer. For a 400×300 box on a Euro pallet, orientation #2 (length aligned with the 800 mm side) usually wins.

Stacking rules that actually matter. EN 13698 says the load shouldn't overhang the pallet edge or be stacked in a pyramid. Practically, every layer must look identical or the stack becomes unstable at forklift speed. If the math gives you a "rotated top layer" — that's a truck-driver problem, not a savings.

Weight vs cube. You'll often be limited by pallet weight (kg) before cube (height) or footprint. The tool reports the binding constraint. If you're cube-limited, ask whether you can use a taller pallet or a mezzanine.

Who this is for. Outbound shipping teams, 3PL operators, anyone who gets invoiced for "pallet space used" on a shared truck.

Square utilisation is the easier metric and the more flattering one. Cubic utilisation tells you how much air you're paying to heat, light, and insure. A facility at 80% square but 25% cubic is leaving rent on the table.

Slotting suggestions by ratio:

• Square > 85%, Cube < 30%: invest in vertical storage (mezzanine, taller racking). Cheap fix.
• Square < 50%, Cube > 60%: floor is congested — you likely have SKU-location overflow. Audit your location master.
• Both < 50%: look at your ABC placement. Fast movers should be at the front, low pick face. Slow movers should be pushed high or far.
• Both > 80%: you're about to outgrow this building. Forecast demand 12 months out before signing a new lease.

Limitations. "Usable floor" is genuinely hard to measure — exclude docks, column exclusion zones, dedicated packing areas, battery charging, blocked fire lanes. If your ERP says you have 2,000 m² and your floor plan says 1,500, believe the floor plan.

Three strategies, three numbers. Serpentine (up one, down the next) is the most common. Return (always back to start) is fast for short orders with few stops. Midpoint (start from the middle) splits serpentine's worst-case in half. The right choice depends on how clustered your orders are.

Order profile matters more than path strategy. A dense order (clustered in 3 aisles) takes 1/3 the time of a sparse order even with the same path strategy. Slotting your SKUs by order affinity — physically placing items that frequently co-order near each other — usually beats any path algorithm.

Pick-to-light and zone picking. If your order has more than ~12 items, you're usually better off with a zone-pick process where each picker covers part of the warehouse, than a single picker walking the whole tour. This calculator won't model that — it's for single-picker scenarios.

Who this is for. Warehouse supervisors setting KPI expectations and WMS implementers deciding which routing strategy to enable.

Why A more than C. An A-class SKU's count error costs you a stockout or overstock on an item that moves. A C-class error sits unnoticed for months. The accuracy-per-dollar gradient is steep; counting all locations equally is the most common cycle-counting mistake.

Target 98%, not 100%. Most operations chasing 100% accuracy spend their last dollar on diminishing returns. At 98% with a robust ABC schedule, you've reduced your inventory-adjustment variance to a level finance can reconcile. Pushing past 98% is usually a process problem (receiving, put-away) masquerading as a count problem.

The labour trap. Cutting count frequency from monthly to quarterly on B items saves real money but only if you also reclassify slow movers into C. Don't slow-cycle B items that are actually behaving like A.

Limitations. This calculator assumes random errors. If you have a systemic problem (one zone consistently wrong, a particular product family miscounted), no frequency will fix it — fix the root cause first.