Plastic Injection Molding Unit Cost Estimator
Calculate production unit costs, NAE aluminum vs steel tooling mold amortization, polymer resin shot weight, clamping tonnage power, and cycle times.
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Material & Job Parameters
Parameter ControlsAuto-Extract Mesh Volume (.STL)
In-Browser WASM ParserDrop 3D .STL file here or click to browse
Pure client-side mesh processing • 0 file upload server latency
Raw material spool/resin bottle cost
Finished model net mass including support waste
Total machine execution time
File slicing, bed prep & post-processing labor
Commercial shop margin
Total Internal Direct Cost:
$0.216 / gram • Total Energy: 0.97 kWh
Recommended Quote Price
$12.26
+$3.18
Cost Composition Breakdown
Total: $9.08100% In-Browser Execution
All material prices, shop rates, and calculation inputs are computed locally in your browser state.
Export itemized quote spreadsheets or generate printable PDF invoices directly from your calculation parameters.
Comprehensive Guide: Plastic Injection Molding Unit Cost Estimator
Plastic injection molding delivers unmatched unit economics at high volumes. Total unit cost consists of mold tooling amortization (fixed tooling cost divided by production volume), polymer resin shot mass (part + runner weight), machine hourly rate (press tonnage power + operator labor), and scrap allowance.
Mathematical Formula Breakdown
Unit Cost = (Mold Tooling Cost / Total Volume) + [((Part Mass + Runner Mass) / 1000) × Resin $/kg] + [(Cycle Time Sec / 3600) × Machine Hourly Rate] × (1 + Defect Rate %).
Industry Pricing Benchmarks
Commodity resins (ABS, PP, PE) cost $1.80–$3.50/kg, while engineering resins (PA66, PEEK, Ultem) range from $8.00 to $65.00/kg. Prototype NAK80 steel molds average $8,000–$25,000, while production hardened P20/H13 steel multi-cavity molds cost $35,000–$150,000+.
Optimization Strategies
- Utilize hot runner manifold systems to eliminate cold runner scrap and reduce shot weight by 15%–30%.
- Maintain uniform wall thickness (2.0–3.0mm) to optimize cooling time, which comprises 60% of total cycle time.
- Select multi-cavity molds (e.g. 4-cavity or 8-cavity) to drastically reduce machine hourly cost per part.
Frequently Asked Questions
How does production volume affect injection molding cost per part?
At low volumes (1k units), tooling amortization dominates the unit cost. At high volumes (50k+ units), material resin mass and cycle time comprise over 85% of total unit cost.
What is shot weight in injection molding?
Shot weight is the total mass of molten plastic injected into the mold per cycle, including the finished part(s), sprue, and runner system.