Pallet Rack Load Capacity Calculator
Estimate the required beam and upright (frame) load capacity for your selective, drive-in, double-deep or cantilever racking — using RMI deflection rules. For planning only; verify with stamped drawings for your site.
How Pallet Rack Load Capacity Is Calculated
Pallet rack capacity is defined by two components working together. Beam capacity is the weight a pair of horizontal beams can safely support across one bay level. Frame (upright) capacity is the total vertical load each upright column carries, based on the combined beam levels and their spacing.
1. Beam capacity per level
Beam capacity = Load per pallet position × Pallet positions per level
Example: the heaviest load is 1,200 lb and you place three pallets per level → 1,200 × 3 = 3,600 lb required beam capacity per level.
2. Frame (upright) capacity
Frame capacity = Beam capacity per level × Number of beam levels
Continuing the example: 3,600 lb × 4 levels = 14,400 lb total upright/frame capacity for that bay.
3. Deflection limit (RMI L/180)
Per RMI (Rack Manufacturers Institute) standards, the maximum allowable beam deflection is L ÷ 180, where L is the beam length. A 96-inch beam may sag no more than 96 ÷ 180 ≈ 0.53 in under load. Exceeding this indicates overloading or possible structural compromise and should be corrected.
Important planning notes
- Published ratings assume ideal, evenly distributed loads, correct beam spacing, proper anchoring and consistent pallet quality — real warehouses rarely stay ideal.
- Capacity drops as beam length increases (longer spans need heavier profiles) and as upright height / level spacing change.
- Always confirm connection type, decking and seismic requirements with a qualified rack engineer before specifying.
- For long or irregular loads (lumber, pipe, steel), see our cantilever racking solutions.
Frequently Asked Questions
What is pallet rack load capacity?
Two parts: beam capacity (weight per pair of beams per level) and frame/upright capacity (total vertical load across all levels). Both must be specified for a safe system.
How do you calculate beam load capacity?
Multiply max load per pallet position by the number of pallet positions per beam level. E.g. 1,200 lb × 3 = 3,600 lb per level.
How do you calculate frame (upright) capacity?
Multiply beam capacity per level by the number of beam levels. E.g. 3,600 lb × 4 = 14,400 lb total frame capacity.
What is the allowable beam deflection?
Per RMI, max deflection is L/180 (L = beam length). A 96-inch beam may deflect no more than ~0.53 in.
Should I add a safety factor?
Yes. Ratings assume ideal conditions; for point loads, seismic zones or impact risk, consult a rack engineer and apply the proper safety factor.