Material weight calculator for plates & blanks
Calculate the weight and volume of a plate or blank from length, width, height and material. Ideal for pre-calculation before milling.
Weight and volume
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Note: All values are non-binding reference figures. Actual values depend on machine, tool, material and conditions. Start conservatively. No liability is accepted for tool breakage, machine damage or machining results.
What the Material Weight Calculator Works Out
The calculator uses the three edge dimensions and the selected material to determine the volume and the resulting weight of a rectangular plate or blank. This lets you estimate, before cutting or milling, how heavy a component will be, what shipping it will involve and how much raw material you need.
The Formula
The basis is a simple physical relationship:
Weight = Volume × Density
The volume of a solid cuboid is calculated from:
Volume = Length × Width × Height
If you convert the dimensions to centimetres and use the density in g/cm³, you get the weight directly in grams. Example: an aluminium plate 20 x 10 x 1 cm has a volume of 200 cm³. Multiplied by the density of 2.70 g/cm³, this gives 540 g, or 0.54 kg.
Density of Common Materials
| Material | Density (g/cm³) |
|---|---|
| Aluminium | 2.70 |
| Steel | 7.85 |
| Stainless steel V2A | 7.90 |
| Brass | 8.50 |
| Copper | 8.96 |
| PMMA (acrylic glass) | 1.18 |
| POM | 1.42 |
| PVC | 1.40 |
| Softwood | 0.50 |
| Hardwood | 0.70 |
| MDF | 0.75 |
| Plywood | 0.68 |
How to Use the Calculator
- Enter the plate dimensions (length, width, height).
- Select the material (the density is applied automatically).
- Read off the weight and volume.
- Subtract holes and pockets: Milled-out material reduces the weight. Calculate the volume of the recess and subtract it from the volume of the solid cuboid.
What to Bear in Mind
The stored densities are reference values for pure materials. Alloys, the moisture content of wood or coatings can cause slight deviations. For complex geometries with many cutouts, subtract the negative volumes one at a time.
You can find more tools in our overview of CNC calculators. Read background information on materials and machining in the Knowledge Centre.
Frequently Asked Questions
How do I calculate the weight of a metal plate?
Multiply the volume (length × width × height) by the density of the material. With dimensions in cm and density in g/cm³, you get the result in grams. A steel plate 20 x 10 x 1 cm weighs 200 cm³ × 7.85 g/cm³ = 1570 g.
What is the density of aluminium?
Aluminium has a density of 2.70 g/cm³. That makes it much lighter than steel (7.85 g/cm³) or stainless steel V2A (7.90 g/cm³).
How do I account for holes and pockets?
Holes and pockets remove material and so reduce the weight. Calculate the volume of the cutout and subtract it from the volume of the solid cuboid before multiplying by the density.
Is the calculated weight exact?
The calculator gives a theoretical value based on the stored standard densities. Alloys, wood moisture or coatings can cause slight deviations from real-world values.
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