Warehouse pick and pack capacity calculator

What this model answers

Batch picking spreads a walking trip across several orders, while packing can remain a per-order task. Adding pickers does not help if the packing budget is already the limiting stage. This model treats the two labor pools independently so that difference remains visible.

Capacity is the largest whole number of orders whose picking and packing work both fit their respective productive person-minute budgets. A binary search handles the step changes created by partial pick batches, instead of dividing by an average that silently ignores the last walk.

The Delivery route time windows calculator traces the outbound schedule after orders are ready. This page establishes a labor budget, while that route model follows travel, waiting and customer service windows. Random waiting needs more than an average capacity budget; the Erlang C staffing waiting probability and service level calculator evaluates a specific no-abandonment steady-state queue.

Measure the right inputs

Enter a measured average number of lines per order and the seconds required per line. Walking time applies once to every started batch. The batch size is an order count, not a quantity of product units or warehouse aisles.

Productive share reduces each employee’s available shift minutes. Do not also inflate measured task times for the same break allowance unless that is intentional. Pickers and packers are separate pools; employees moving between stages need a different allocation model.

Read the result in context

The workload table compares the entered order count with each stage budget, while the headline searches capacity independently of that entered workload. A negative slack means that stage cannot complete the entered amount within its assumed labor budget.

Pooling person-minutes assumes work can be divided effectively among employees. It does not schedule the first packed order, model queue buildup or ensure every order is ready by a common dispatch deadline. Capacity under a time-phased schedule can be lower.

Work through the numbers

At three lines and twenty seconds per line, one hundred orders require one hundred picking minutes. Ten batches add fifty walking minutes, producing 150 person-minutes of picking work.

Two pickers each have 360 productive minutes at a 75 percent share of a 480-minute shift. One packer has 360 minutes and needs two minutes per order, so packing caps the example at 180 orders even though picking could handle more.

Where the model stops

Work-content estimate with perfect pooling within each stage, not a precedence schedule, queueing model or staffing guarantee.

The capacity search is capped at ten million orders. Real congestion, replenishment, breaks, quality checks and travel layout need explicit allowances or a separate operational study.