Calculator Inputs
Example Data Table
| Location | Share % | Capacity/day | Transit days | Pick/pack min | Base ship | Per kg | Handling | Reliability % |
|---|---|---|---|---|---|---|---|---|
| North Hub | 45 | 140 | 2.1 | 28 | 3.20 | 1.10 | 0.95 | 96 |
| Central Hub | 35 | 120 | 1.7 | 32 | 3.40 | 1.05 | 1.05 | 94 |
| South Partner | 20 | 90 | 2.9 | 40 | 2.80 | 1.35 | 0.85 | 92 |
Formula Used
- Effective Capacity = Capacity × (1 − Buffer%)
- Time (days) = Transit days + (Pick&pack minutes ÷ 60 ÷ 24)
- Cost per order = Handling + Base ship + (Per-kg × Avg weight) + Regional surcharge
- Planned orders = Orders/day × (Share ÷ Sum of shares)
- Fulfilled orders = min(Planned orders, Effective capacity)
- Normalize Cost and Time across locations to 0–1.
- Score = CostFocus×CostNorm + SpeedFocus×TimeNorm + ReliabilityEmphasis×(1−Reliability)
- Leftover demand is redistributed to lowest-score locations with spare capacity.
- Weighted averages use Fulfilled orders as weights.
- On-time estimate = Reliability × SLA factor, reduced 15% per late day.
How to Use This Calculator
- Enter your Orders per day, average weight, and your SLA target.
- Set Cost focus and Reliability emphasis to match your strategy.
- Apply a Capacity buffer to reserve operational headroom.
- Add each location with transit time, handling, and shipping costs.
- Click Calculate to see allocation, costs, and service outcomes.
- Use Download CSV or Download PDF for sharing.
Network Inputs That Drive Allocation
This calculator starts with daily order demand, then distributes it using your location shares. Shares are normalized, so a 40/40/40 entry becomes 33.3% each. Capacity is reduced by the buffer percentage to create effective capacity, which protects against labor gaps and peak volatility. Planned orders are capped at effective capacity, and any shortfall is reported as unfulfilled volume for quick escalation.
Balancing Cost and Speed With Priority Weights
Each node receives a score built from normalized cost and time, plus a reliability penalty. Cost and time are scaled between the best and worst nodes, keeping the score comparable across scenarios. Cost focus sets the cost weight from 0 to 100, while speed focus becomes the remainder. When cost focus is 70, the model favors cheaper lanes even if transit is slower. Reliability emphasis increases the penalty for lower performance, helping you avoid allocations that look cheap but trigger churn.
Service Risk and On‑Time Estimation
Delivery time is computed as transit days plus pick-and-pack minutes converted into days. The on-time estimate multiplies reliability by an SLA factor: when a location is late, the factor drops 15% per day beyond the SLA target. Compare the network’s weighted average delivery days to your SLA to see whether you need faster hubs, tighter cutoffs, or more proximity.
Split Shipments and Hidden Margin Erosion
Splits are common when inventory is fragmented across nodes. Enable split shipment modeling to estimate extra parcels from a split rate percentage. The calculator adds incremental packaging and incremental shipping cost per split, then rolls that into adjusted daily spend and adjusted average cost per fulfilled order. Use this to justify consolidation, safety stock, or smarter routing rules.
Operational Reporting and Scenario Planning
After calculation, the summary panel shows fulfilled volume, utilization, cost per order, delivery time, and score by location. Watch utilization above 85% as an early warning for missed cutoffs and backlogs. Download CSV for analysts and PDF for leadership updates and vendor reviews. Run scenarios by adjusting buffer, shifting shares, or adding a partner node, then track how unfulfilled orders, on-time rate, and daily cost move together. This turns planning into repeatable governance.
FAQs
Q: How do I choose demand share percentages?
Use recent order distribution by region or store. If unsure, start equal shares, then adjust after seeing capacity gaps and cost. Shares are normalized, so focus on relative proportions not exact 100.
Q: What does capacity buffer represent?
It reserves operational headroom for absenteeism, carrier pickup variability, and rework. A 10% buffer means a site rated at 1,000 orders/day is planned as 900 for allocation.
Q: Why is adjusted average cost higher than average cost?
Adjusted cost includes split shipment extras and reflects total spend per fulfilled order. If splits are disabled or set to zero, both averages match.
Q: Can I model a new 3PL before contracting?
Yes. Add a location with estimated transit days, reliability, handling, and rate card values. Run scenarios with conservative assumptions, then compare its score and utilization against existing nodes.
Q: How is on-time rate different from SLA days?
SLA days is your target promise window. On-time rate estimates the probability of meeting it, combining reliability and a lateness penalty when average time exceeds SLA.
Q: What should I do when unfulfilled volume appears?
Increase effective capacity by lowering buffer, adding labor, or adding a node. Alternatively reduce demand, shift shares, or relax SLA. Recalculate to confirm unfulfilled becomes zero and utilization drops to a stable level.