Steel Plate Weight Calculator
Enter thickness, width, length and quantity values and instantly find the weight of S690QL, S700MC and general steel plate. The calculation is based on the 7.85 g/cm³ density of steel.
Steel Plate Weight Calculator
Enter the plate dimensions in millimetres; the result is calculated in kilograms.
Calculation History
Your recent calculations are stored in your browser; you can request a price quote for each row with a single tap.
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| Material | Thickness (mm) | Width (mm) | Length (mm) | Quantity | Weight (kg) | Delete | Get Price |
|---|---|---|---|---|---|---|---|
| Total Weight | 0 kg | ||||||
How Is It Calculated?
Plate weight is based on the volume × density principle. For steel, the density is taken as 7.85 g/cm³ (7850 kg/m³). When all dimensions are entered in millimetres, the practical formula is:
The 0.00000785 factor here is the constant obtained from the mm³ → kg conversion of steel's density (7.85 g/cm³ = 0.00000785 kg/mm³). For multiple pieces, this unit weight is multiplied by the quantity.
Reference Densities by Material
Different materials have different densities. The values below are the references used as the multiplier in the weight calculation:
| Material | Density (g/cm³) | Density (kg/m³) | Note |
|---|---|---|---|
| Structural Steel (S690QL, S700MC, S355) | 7.85 | 7850 | Standard assumption for carbon steels |
| Stainless Steel (AISI 304/316) | ~8.0 | ~8000 | Varies with nickel-chromium alloy |
| Aluminium | ~2.70 | ~2700 | About one third of steel |
| Copper | ~8.96 | ~8960 | Electrical/thermal conduction applications |
| Brass | ~8.50 | ~8500 | Copper-zinc alloy |
Note: The calculator above is configured for steel (7.85 g/cm³). For other materials, the weight can be approximated by multiplying with the relevant density ratio.
Frequently Asked Questions
How is plate weight calculated?
Plate weight is the product of volume × density. Practical formula:
Weight (kg) = Thickness (mm) × Width (mm) × Length (mm) × 0.00000785
This factor is derived from the 7.85 g/cm³ (7850 kg/m³) density of steel. When all dimensions are entered in millimetres, the result comes out directly in kilograms. For multiple pieces, multiply the result by the quantity.
What is the density of steel?
The density of structural steel is taken as approximately 7.85 g/cm³, that is 7850 kg/m³. Most carbon steels, including S690QL and S700MC, are at this value.
For comparison: stainless steel has a density of about 8.0 g/cm³, aluminium 2.70 g/cm³ and copper 8.96 g/cm³.
Is the calculated weight exact?
The calculated value is a theoretical estimate. The actual weight can vary slightly due to thickness tolerances, cutting losses, surface coating and density differences.
For exact tonnage, weighing or using the values in the EN 10204 3.1 inspection certificate as the basis is recommended.
How do I find the total weight for multiple pieces?
After calculating the single-piece weight, multiply it by the quantity. When you enter the number of pieces in the Quantity field of the calculator, the total weight is computed automatically.
For projects with multiple items of different dimensions, each row is added to the history and the Total Weight value below the table sums all items.
Done Calculating? Get a Price Quote Now
Once you have completed your weight calculation, contact us for current pricing and stock information. We deliver S690QL and S700MC plates ex-stock, including cutting and bending.