| Scenario | Good units | Materials mode | Labor mode | Charts |
|---|---|---|---|---|
| Default run | 1,000 | Detailed list + scrap + freight | Regular + overtime + burden | Pie, bar, and cost curve |
- Materials base = Sum(qty × unit cost) or a single total
- Freight-in = Materials base × (Freight% / 100)
- Materials incl. scrap = (Materials base + Freight-in) × (1 + Scrap% / 100)
- Labor wages = Regular hours × rate, plus optional overtime
- Labor burden = Labor wages × (Burden% / 100)
- Direct labor = Labor wages + Labor burden
- Machine cost = Run + Maintenance + Energy
- Total manufacturing cost = Sum of all categories
- Unit cost = Total manufacturing cost ÷ Good units
- COGM = Total manufacturing cost + Beg WIP − End WIP
- COGS = COGM + Beg FG − End FG
- Price = Margin or markup mode, then profit per unit
- Enter good units produced for your batch.
- Choose materials mode, then add scrap and freight-in.
- Pick labor mode, include overtime and burden if needed.
- Enter machine hours, plus maintenance and energy.
- Set overhead and allocated fixed costs for the same period.
- Optionally add inventories for COGM/COGS.
- Select margin or markup to estimate price and profit.
- Press Calculate to update tables and Plotly charts.
- Use CSV/PDF exports to save scenarios.
Cost structure drivers
Manufacturing cost is built from materials, labor, machine time, overhead, and fixed allocations. This calculator totals each category, then divides by good units to produce unit cost. It also includes setup, inspection, warranty, rework, packaging, and shipping charges. Because fixed costs spread across volume, the unit-cost curve shows how batches can reduce per-unit expense when variable rates stay steady.
Material variance controls
Use the detailed materials list to model bill-of-material lines as quantity times unit cost. Add freight-in as a percent of material spend, then apply scrap rate to cover yield losses and handling waste. For example, a 1.5% freight factor and 3% scrap uplift increase effective materials cost before any labor. Track supplier price changes and scrap trends monthly to separate purchasing variance from process variance.
Labor and burden planning
Direct labor combines wages and a burden percentage for benefits, payroll taxes, and allowances. If overtime is required, the calculator applies a multiplier to overtime hours, then burdens the total wages. A burden of 18% turns $10,000 wages into $11,800 direct labor. Compare regular versus overtime scenarios to quantify schedule pressure, then adjust staffing, training, or shifts to protect margin.
Machine utilization and energy
Machine cost can include run rate, maintenance per machine hour, and energy consumption modeled as kWh per machine hour times the energy rate. A line running 120 hours at $22 per hour creates $2,640 of run cost before maintenance and energy. For energy-intensive lines, small changes in kWh assumptions can shift unit cost materially.
Overhead allocation and pricing
Overhead may be allocated as a percent of direct labor, a rate per machine hour, or a fixed batch amount. Select the method that matches your accounting policy, then review COGM and COGS using optional WIP and finished goods entries. If units sold differ from units produced, inventory fields help reconcile costs. Use margin or markup outputs to set a selling price, then evaluate gross profit and operating profit after selling and admin costs.
FAQs
What is the difference between total manufacturing cost and unit cost?
Total manufacturing cost sums all batch expenses. Unit cost divides that total by good units produced, so scrap, fixed allocations, and setup costs are spread across each unit.
When should I use margin versus markup pricing?
Use margin when you target profit as a percent of selling price. Use markup when you apply a percent on top of cost. The calculator supports both and shows the implied selling price.
How do scrap and freight-in change materials cost?
Freight-in adds a percent to material spend first. Scrap then uplifts the materials total to cover yield loss. Higher scrap rates increase unit cost even if purchase prices stay unchanged.
Which overhead allocation method is best?
Choose the base your accounting uses. Percent-of-labor fits labor-driven work, per-machine-hour fits equipment-driven lines, and fixed overhead works when you assign a set amount per batch.
How do COGM and COGS relate to inventory entries?
COGM adjusts manufacturing cost for beginning and ending work-in-process. COGS then adjusts COGM for beginning and ending finished goods. Keeping inventory fields at zero shows a pure batch view.
Can I export charts in the PDF report?
Yes. The PDF export embeds images of the interactive Plotly charts, plus summary and breakdown tables. Use it to share scenarios with stakeholders or attach results to cost files.