Free Engineering Tool
ShrinkPro Shrinkage Calculator
Calculate precise mold cavity dimensions for 30+ injection molding resins. Select your material, enter the desired part dimension, and get instant shrinkage compensation values.
Calculate Shrinkage
Complete Material Shrinkage Reference Table
Shrinkage rates for 30+ common injection molding resins. Filter by category or search by name.
| Material | Abbreviation | Category | Min % | Typical % | Max % |
|---|---|---|---|---|---|
| Polypropylene (Homopolymer) | PP-H | Commodity | 1 | 1.8 | 2.5 |
| Polypropylene (Copolymer) | PP-C | Commodity | 1 | 1.5 | 2 |
| PP 20% Glass Filled | PP-GF20 | Commodity | 0.4 | 0.7 | 1 |
| High Density Polyethylene | HDPE | Commodity | 1.5 | 2.5 | 4 |
| Low Density Polyethylene | LDPE | Commodity | 1.5 | 2.5 | 3.5 |
| Polystyrene (GPPS) | GPPS | Commodity | 0.3 | 0.5 | 0.6 |
| High Impact Polystyrene | HIPS | Commodity | 0.4 | 0.5 | 0.7 |
| PVC (Rigid) | PVC-R | Commodity | 0.1 | 0.3 | 0.5 |
| PVC (Flexible) | PVC-F | Commodity | 1 | 2 | 3 |
| ABS | ABS | Engineering | 0.4 | 0.5 | 0.7 |
| ABS/PC Blend | ABS/PC | Engineering | 0.5 | 0.6 | 0.7 |
| Polycarbonate | PC | Engineering | 0.5 | 0.6 | 0.7 |
| PC 20% Glass Filled | PC-GF20 | Engineering | 0.2 | 0.3 | 0.4 |
| Nylon 6 (PA6) | PA6 | Engineering | 0.7 | 1 | 1.5 |
| Nylon 66 (PA66) | PA66 | Engineering | 0.8 | 1.2 | 1.5 |
| PA6 30% Glass Filled | PA6-GF30 | Engineering | 0.3 | 0.4 | 0.5 |
| PA66 33% Glass Filled | PA66-GF33 | Engineering | 0.2 | 0.3 | 0.5 |
| Acetal (POM) Homopolymer | POM-H | Engineering | 1.8 | 2.1 | 2.5 |
| Acetal (POM) Copolymer | POM-C | Engineering | 1.5 | 1.9 | 2.2 |
| PBT Polyester | PBT | Engineering | 1.3 | 1.6 | 2 |
| PBT 30% Glass Filled | PBT-GF30 | Engineering | 0.3 | 0.5 | 0.7 |
| PET Polyester | PET | Engineering | 1 | 1.5 | 2.5 |
| PPO/PPE Modified | mPPO | Engineering | 0.5 | 0.6 | 0.7 |
| PMMA (Acrylic) | PMMA | Engineering | 0.2 | 0.5 | 0.8 |
| PEEK | PEEK | Specialty | 1 | 1.2 | 1.5 |
| PEEK 30% Glass Filled | PEEK-GF30 | Specialty | 0.3 | 0.4 | 0.5 |
| PPS | PPS | Specialty | 0.6 | 1 | 1.4 |
| PPS 40% Glass Filled | PPS-GF40 | Specialty | 0.2 | 0.3 | 0.4 |
| PEI (Ultem) | PEI | Specialty | 0.5 | 0.6 | 0.7 |
| LCP | LCP | Specialty | 0.1 | 0.2 | 0.5 |
| PSU (Polysulfone) | PSU | Specialty | 0.6 | 0.6 | 0.7 |
| TPE (Shore A 50 to 80) | TPE | Elastomer | 1 | 2 | 3 |
| TPU (Shore A 80 to 95) | TPU | Elastomer | 0.8 | 1.3 | 2 |
| Silicone (LSR) | LSR | Elastomer | 2 | 3 | 4 |
How to Use the Shrinkage Calculator
Select Material
Choose from 30+ resins organized by category: commodity, engineering, specialty, and elastomer thermoplastics.
Enter Dimension
Input the desired final part dimension in millimeters. This is the dimension you want after the part has cooled and shrunk.
Read Results
Get the required mold cavity dimension along with minimum and maximum shrinkage compensation values for tolerance planning.
Need Expert Help?
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