Multi-Warehouse Shipping Optimization API

The Multi-Warehouse Challenge

Split Inventory

When items in a single order are spread across multiple warehouses, fulfillment complexity multiplies.

Excess Packages

Without optimization, each warehouse ships separately, leading to more packages than necessary for a single order.

Higher Shipping Costs

More packages means more dimensional weight charges, more handling fees, and higher last-mile delivery costs.

Combinatorial Complexity

With multiple warehouses, box sizes, and item combinations, the number of possible fulfillment strategies grows exponentially.

Illustrative Example

Example Scenario: 3-Item Order Across 2 Warehouses

Consider a hypothetical order with 3 items. Item A and Item B are stocked in Warehouse 1, while Item C is only available in Warehouse 2. Warehouse 1 also stocks Item C, but with limited quantity.

Manual Approach

Each warehouse ships its own items independently.

Warehouse 1: Ships Item A + Item B in Box 1
Warehouse 2: Ships Item C alone in Box 2

Result: 2 packages shipped

Hypothetical cost: $18.50 + $12.00

Total: $30.50

StoaPack Optimized

The API evaluates whether consolidating items reduces total cost.

Warehouse 1: Ships Item A + Item B + Item C in one box (Item C is in stock here too)

Result: 1 package shipped

Hypothetical cost: $22.00

Total: $22.00

The numbers above are hypothetical and for illustration purposes only. Actual savings depend on order composition, warehouse locations, carrier rates, and inventory availability.

How It Works

Submit Order Data

Send item dimensions, weights, quantities, and your warehouse inventory via a single API call. Include available box sizes per warehouse.

Inventory Mapping

The algorithm maps which items are available at which warehouses and identifies consolidation opportunities across locations.

Optimization Engine

StoaPack evaluates fulfillment strategies to find the combination that minimizes total packages, wasted space, or shipping cost.

Actionable Results

Receive a per-warehouse packing plan with box selection, item placement coordinates, and any items that could not be fulfilled.

Comparison: Fulfillment Approaches

Capability	Manual Process	Basic Cartonization	StoaPack
Box size selection	Operator judgment	Single-warehouse optimization	Cross-warehouse optimization
Multi-warehouse awareness	None	None	Full inventory mapping
Package consolidation	Ad hoc	Within single warehouse	Across all warehouses
3D item placement	No	Basic volume calculation	Full 3D coordinate placement
AI custom instructions	No	No	Natural language rules
Optimization goal selection	No	Limited	Min boxes, volume, or cost
Hazmat compliance	Manual lookup	No	Built-in 49 CFR / IATA DGR

Is This Right For You?

Good Fit

You fulfill orders from 2 or more warehouse locations
Orders frequently contain items spread across warehouses
You want to reduce the number of packages per order
You have a WMS or OMS that can consume API responses
Shipping costs are a significant part of your operating expenses

May Not Be Needed

You ship from a single warehouse only
All items in every order are always co-located
You ship very few orders per day (manual review is feasible)
Your items are uniform size and always fit in one standard box

Frequently Asked Questions

There is no hard limit on the number of warehouses per request. Each warehouse object includes its own inventory and available box sizes, and the algorithm evaluates all combinations to find the optimal fulfillment strategy.

Items that cannot be fulfilled from any warehouse are returned in the unfitted_items array of the API response. This allows your system to handle backorders or notify the customer without the entire request failing.

Yes. Each warehouse in the request has its own available_boxes array. This means Warehouse A can use a different set of box sizes than Warehouse B, and the algorithm accounts for this when determining the optimal packing plan.

Yes. Hazmat segregation rules, quantity limits, and shipping mode constraints are applied on top of the multi-warehouse optimization. Incompatible materials will be separated into different packages regardless of warehouse assignment.

You can optimize for minimum number of boxes, minimum wasted volume, or minimum cost (when box pricing is provided). The optimization goal applies across all warehouses in the fulfillment plan.

Yes. The custom_instructions field accepts plain English rules that are applied during optimization. For example, you could instruct the API to "prefer shipping from the closest warehouse" or "keep fragile items on top."

Multi-Warehouse Shipping Optimization