Density converts material volume into mass. Use a grade-specific datasheet for final engineering work; the rounded values below are planning references, not chemical or product acceptance limits.
| Material / planning reference | Density (g/cm³) | Density (kg/m³) |
|---|---|---|
| Carbon steel, approximate | 7.85 | 7850 |
| 304L stainless, typical | 7.9 | 7900 |
| 316L stainless, typical | 8.0 | 8000 |
| 6061 aluminum, rounded | 2.7 | 2700 |
| Copper, approximate | 8.96 | 8960 |
| Commercially pure titanium, approximate | 4.51 | 4510 |
| Magnesium, approximate | 1.74 | 1740 |
| Zinc, approximate | 7.14 | 7140 |
Unit conversion without hidden factors
One g/cm³ equals 1000 kg/m³ and also equals one kg/dm³. Mass in kg = volume in m³ × density in kg/m³. For dimensions in mm, divide the volume in mm³ by one billion before multiplying by kg/m³. A density of 7.85 g/cm³ is not 7.85 kg/m³.
For example, a solid block measuring 100 × 50 × 10 mm has a volume of 50,000 mm³, or 0.00005 m³. At the planning carbon-steel density it weighs 0.3925 kg; at 2700 kg/m³ it weighs 0.135 kg. This comparison uses identical geometry, not equal strength or stiffness.
Choose the right volume and material
A bounding-box volume includes holes, pockets and cutouts that may not contain metal. CAD net volume is usually better for a finished part, while purchased stock volume is useful for material budgeting. Welds, inserts and coatings need separate treatment.
Stainless steel is not one density, and a cast alloy need not match wrought stock. The producer references below show why naming the grade is preferable to selecting only “steel” or “aluminum.” For exact traceability, record the datasheet revision and the density used alongside your calculation.
What a mass estimate cannot establish
Equal mass does not mean equal mechanical performance. Density does not replace yield strength, modulus, fatigue data, corrosion behavior or a design calculation. Weigh assemblies when handling capacity or shipping limits are close. For rectangular sheets, the linked tool performs the volume and unit arithmetic and accepts your own density.
Convert the same density into inch units
Using 1 in = 25.4 mm and 1 lb = 453.59237 g, density in lb/in³ = density in g/cm³ × 0.036127292. The rounded results below convert the planning values already listed; they do not add precision to the underlying material data.
| Planning material | g/cm³ | lb/in³, rounded |
|---|---|---|
| Carbon steel | 7.85 | 0.2836 |
| 304L stainless | 7.90 | 0.2854 |
| 316L stainless | 8.00 | 0.2890 |
| 6061 aluminum | 2.70 | 0.09754 |
| Copper | 8.96 | 0.3237 |
| Commercially pure titanium | 4.51 | 0.1629 |
For traceability, the 7.9 and 8.0 g/cm³ stainless references correspond to the selected Prodec 304L/4307 and 316/4404 rows in Outokumpu’s Prodec datasheet, physical properties. Record the exact grade and source revision for a released calculation rather than calling every stainless alloy 8.0.
Subtract a through-hole before calculating finished mass
A hypothetical 100 × 50 × 10 mm plate has 50,000 mm³ gross volume. A 20 mm through-hole removes π × 10² × 10 = 3,141.59 mm³. Net volume is 46,858.41 mm³. At 7,850 kg/m³, estimated mass is 0.36784 kg rather than the solid blank’s 0.39250 kg: a difference of about 24.66 g.
Use the blank mass for purchased-stock accounting and the net mass for the ideal finished geometry; neither includes packaging, inserts or coating. A CAD volume check is useful for complex pockets, but its assigned material must still match the actual alloy and condition.
Content updated October 8, 2026. Sources and numerical examples are explained above; examples are not production test results. Editorial method · Report a correction.
References and verification
Original explanations and worked examples by MfgWorkbench. Sources below support the stated concepts or selected reference data; they do not certify every example or a production application.
- Outokumpu — Prodec stainless grade properties
- Hydro — alloy 6061 data sheet
- Royal Society of Chemistry — periodic table element properties
For a correction, send the page URL, the affected value and supporting documentation through our contact page.