Material Engineering2D

Steel Plate Weight Calculator

Calculate steel plate weight from length, width, and thickness with various steel grades.

Inputs
Enter your values below
Result
Plate Weight
Enter values and click Calculate
Loading visualization
Formula
length × width × thickness × density
Result unit: kg

Weight = L × W × T × ρ. All dimensions converted to meters, density in kg/m³, result in kg.

Introduction

Calculate the weight of a flat steel plate from its dimensions and material density. Essential for structural steel estimating, shipping weight calculations, and material ordering. The quick rule for carbon steel is 7.85 kg per square meter per millimeter of thickness - see the tables below for common plate weights. This page is dedicated to flat plate and sheet only (Weight = L x W x T x density); for round bar, pipe or structural beam weight use the Steel Weight Calculator hub.

How This Calculator Works

Weight = L × W × T × ρ. All dimensions converted to meters, density in kg/m³, result in kg.

Step-by-step process:

  1. Enter your input values in the calculator above
  2. The engine converts all inputs to SI base units (meters, kg, Pa)
  3. The formula is evaluated: length * width * thickness * density
  4. Result is formatted with the appropriate unit and precision

Calculation Example

A 2000mm × 1000mm × 10mm carbon steel plate weighs 157 kg.

Inputs: length=2000, width=1000, thickness=10, density=7850
Result: 157 kg

Steel Plate Weight per Square Meter

For carbon steel, plate weight per unit area = thickness (mm) x 7.85 kg/m2/mm:

| Thickness (mm) | kg/m2 | lb/ft2 |

|---|---|---|

| 3 | 23.6 | 4.83 |

| 5 | 39.3 | 8.04 |

| 6 | 47.1 | 9.65 |

| 8 | 62.8 | 12.9 |

| 10 | 78.5 | 16.1 |

| 12 | 94.2 | 19.3 |

| 16 | 125.6 | 25.7 |

| 20 | 157.0 | 32.2 |

| 25 | 196.3 | 40.2 |

| 30 | 235.5 | 48.2 |

| 40 | 314.0 | 64.3 |

| 50 | 392.5 | 80.4 |

These values assume carbon steel density 7850 kg/m3. Multiply by 1.010 for SS304 and 1.018 for SS316.

Common Plate Sizes and Weights

Standard 4 ft x 8 ft plate (1220 x 2440 mm):

| Thickness (mm) | Weight per plate (kg) |

|---|---|

| 3 | 70.1 |

| 5 | 116.8 |

| 6 | 140.2 |

| 8 | 186.9 |

| 10 | 233.7 |

| 12 | 280.4 |

| 16 | 373.9 |

| 20 | 467.4 |

| 25 | 584.3 |

European standard plate is often 1500 x 3000 mm or 2000 x 6000 mm; enter the actual dimensions in the calculator above for exact values.

Unit Conversion

| Convert | Multiply by |

|---|---|

| kg to lb | 2.20462 |

| kg/m2 to lb/ft2 | 0.204816 |

| lb/ft2 to kg/m2 | 4.88243 |

Example: a 2000 x 1000 x 10 mm carbon steel plate = 157 kg = 157 x 2.20462 = 346 lb. Galvanized plate adds roughly 3% weight for the zinc coating.

How to Order Steel Plate

When ordering steel plate you typically specify: grade (e.g. A36, S275, SS304), thickness (mm or inches), width and length (metric sheets are often 1500 x 3000 mm or 2000 x 6000 mm; US plates are often 4 ft x 8 ft), and quantity. Plate is usually supplied with sheared or flame-cut edges. Estimate the shipped weight with the calculator, then add about 3% if the plate is hot-dip galvanized. For pressure vessel plate, order to the specified grade standard (e.g. ASTM A516) and verify the mill certificate on delivery.

Engineering Applications

  • Structural steel estimating
  • Shipping weight calculation
  • Material ordering
  • Load estimation
  • CNC plasma and laser cutting cost estimation
  • Flame-cut blank and fabrication quoting
  • Shipbuilding and offshore plate ordering
  • Floor plate and access platform design

Frequently Asked Questions

What density does carbon steel use?

Carbon steel density is approximately 7850 kg/m³ (7.85 g/cm³). Stainless steel 304 is slightly higher at 7930 kg/m³.

How do I calculate weight per square meter?

Weight per m² = thickness (m) × density (kg/m³). For 10mm steel: 0.01 × 7850 = 78.5 kg/m².

How much does a 4x8 steel plate weigh?

A standard 4 ft x 8 ft (1220 x 2440 mm) carbon steel plate weighs 233.7 kg at 10 mm thickness, 140.2 kg at 6 mm, and 467.4 kg at 20 mm. Use the plate weight table in this calculator for the full range.

How much does 1 square meter of 10mm steel plate weigh?

A 10 mm carbon steel plate weighs 78.5 kg/m2 (10 x 7.85). Stainless steel 304 weighs about 79.3 kg/m2 at the same thickness.

How much extra weight does galvanizing add to steel plate?

Hot-dip galvanizing typically adds about 3% to steel plate weight, depending on coating thickness (commonly 70-85 microns per face). The zinc coating weighs roughly 0.5-0.6 kg/m2 for standard G90/galvanized classes.

How much does a 4x8 foot 1/4 inch steel plate weigh?

A 1/4 inch (6.35 mm) 4 ft x 8 ft carbon steel plate weighs about 6.35 x 7.85 = 49.8 kg/m2 over an area of 2.97 m2, giving roughly 148 kg (326 lb). In practice the 6 mm row of the common plate table (140.2 kg) is used for estimating. Enter the exact thickness in the calculator above for a precise value.

Do you also calculate round bar or pipe weight?

No - this page is dedicated to flat steel plate and sheet (Weight = L x W x T x density). For solid round bar use the round bar weight calculator (pi/4 x D^2 x L x density), for pipe use the pipe weight calculator (pi x (OD - WT) x WT x L x density), and for beams use the steel weight calculator hub - all are linked from the related section above.

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Engineering Disclaimer: Calculations are for reference and educational purposes only. Always verify results independently for engineering design. See full disclaimer.
Reviewed by: Industrial Engineering Team
References: ASME B31.3, ASTM A36, Perry's Chemical Engineers' Handbook