About this calculator

Compare uniform back-to-back rack banks inside an unobstructed rectangle. Wall reservations, full bay pitch, bank depth and all outer and interior aisles define the grid.

Inputs

How to use this calculator

Alternative room scenario

  1. Clear rectangular room length (ft)Use an unobstructed rectangle after accounting for columns, doors and reserved spaces.
  2. Clear rectangular room width (ft)This model assumes the entire rectangle is available for the stated grid.

Shared inputs

  1. Additional reserved strip at every wall (ft)Removed at both ends of both room axes.
  2. Full bay pitch including uprights (ft)A repeated module length, not just clear beam length.
  3. Depth of one rack row (ft)Enter the approved loaded depth/envelope for this model.
  4. Gap between back-to-back rows (ft)User-required gap; no standard flue or fire clearance is inferred.
  5. Operating aisle width (ft)One aisle at both outer sides and between every bank; user-approved clearance.
  6. Approved position levelsIncludes the ground level; no structural calculation is made.
  7. Pallet positions per bay per levelAlready validated for the chosen beam/loaded pallet geometry.
  8. Room grid directionNo mixed directions or irregular-layout solver.

Enter the shipment or scenario values, then select Calculate result.

Method

Formula and variables

Net axes = room axes − 2 × edge strip. Back-to-back bank depth = 2 × row depth + back gap. For each allowed direction: bays/row = floor(net along ÷ bay pitch); banks = max(0, floor((net across − aisle) ÷ (bank depth + aisle))). Positions = banks × 2 rows × bays × positions/bay/level × levels. Adjacent banks share aisles; both outer aisles are included.

Clear rectangular room length (ft)
Use an unobstructed rectangle after accounting for columns, doors and reserved spaces.
Clear rectangular room width (ft)
This model assumes the entire rectangle is available for the stated grid.
Additional reserved strip at every wall (ft)
Removed at both ends of both room axes.
Full bay pitch including uprights (ft)
A repeated module length, not just clear beam length.
Depth of one rack row (ft)
Enter the approved loaded depth/envelope for this model.
Gap between back-to-back rows (ft)
User-required gap; no standard flue or fire clearance is inferred.
Operating aisle width (ft)
One aisle at both outer sides and between every bank; user-approved clearance.
Approved position levels
Includes the ground level; no structural calculation is made.
Pallet positions per bay per level
Already validated for the chosen beam/loaded pallet geometry.
Room grid direction
No mixed directions or irregular-layout solver.

Interpret the result

The result is a geometry count for entered approved modules and levels. It does not provide structural rack design or required fire, sprinkler or egress clearances.

Outputs: Rack positions and dimensions by room scenario

Idealized unobstructed rectangular geometry for back-to-back banks. No single-row wall racks, mixed layouts, structural/beam capacity, sprinkler/flue/egress design, seismic review, truck turning envelope or building-code approval. Enter dimensions/levels already reviewed for the intended equipment; a grid estimate is not a rack design.

Worked example

Check the arithmetic

This example uses the starting values shown above. The arithmetic below is calculated independently of the interactive result.

Work through the calculation

  1. Net room = (100 − 2 × 5) × (80 − 2 × 5) = 90 × 70 ft; bank depth = 2 × 3.5 + 1 = 8 ft.
  2. Lengthwise: floor((70 − 12) ÷ (8 + 12)) = 2 banks; floor(90 ÷ 9) = 10 bays. Positions = 2 × 2 × 10 × 2 × 3 = 240.
  3. Rotated: 3 banks × 2 rows × 7 bays × 2 positions × 3 levels = 252 positions.

Compare the displayed result

Expected displayed result: 252 positions

FAQs

Are aisles included outside the outer banks?

Yes. Both outer operating aisles are included as well as shared aisles between banks. The wall reservation is an additional strip.

Example inputs and options

Starting values are examples unless a field identifies a dated rule. Unit selectors convert only fields marked for conversion. Rates and model options keep the units and basis shown in their labels.

Clear rectangular room length (ft)
Example: 100
Clear rectangular room width (ft)
Example: 80
Additional reserved strip at every wall (ft)
Example: 5
Full bay pitch including uprights (ft)
Example: 9
Depth of one rack row (ft)
Example: 3.5
Gap between back-to-back rows (ft)
Example: 1
Operating aisle width (ft)
Example: 12
Approved position levels
Example: 3
Pallet positions per bay per level
Example: 2
Room grid direction
Example: Compare lengthwise and 90° whole-grid directionsOptions: Bays run along the entered length only; Compare lengthwise and 90° whole-grid directions