Thermoplastic Injection Molding Calculator
Estimate material usage, costs, and production rates for your injection molding process. Input your part and process parameters below.
Enter your project details and click “Calculate Properties”
Understanding the Calculations
This calculator provides estimates for key injection molding parameters. Here’s a brief overview of what’s calculated:
- Total Part Volume per Shot: Part Volume × Number of Cavities.
- Total Volume per Shot: Total Part Volume per Shot + Runner & Sprue Volume. This is the total plastic volume injected each cycle.
- Shot Weight: Total Volume per Shot × Material Density. This is the weight of plastic used per cycle.
- Material Cost per Shot: Shot Weight × Material Cost (per unit weight).
- Material Cost per Part: Material Cost per Shot / Number of Cavities. This gives you the raw material cost for one finished part.
- Parts per Hour: (3600 seconds / Cycle Time in seconds) × Number of Cavities. This estimates your production output rate.
- Total Shots for Run: Production Run Size / Number of Cavities (rounded up).
- Total Material Needed: Shot Weight × Total Shots for Run.
- Total Material Cost for Run: Total Material Needed × Material Cost (per unit weight).
- Estimated Production Time: Total Shots for Run × Cycle Time.
Note: These calculations assume 100% material utilization (no scrap beyond runner/sprue, which is accounted for) and consistent cycle times. Actual production may vary due to machine efficiency, startup/shutdown, quality checks, and other real-world factors.