Simple Formula to Calculate the Weight of Steel Rebar Per Meter

Simple Formula to Calculate the Weight of Steel Rebar Per Meter

Calculating the weight of steel reinforcement bars (rebar) is essential for construction projects to estimate material requirements, costs, and logistics. Using a straightforward formula, contractors, engineers, and suppliers can quickly determine rebar weight per meter. As a trusted supplier, Ruixiang Steel provides high-quality rebar and practical guidance to simplify this process for your projects.

Understanding the Basic Formula
The standard formula to calculate the weight of steel rebar per meter is based on its diameter and the density of steel. The formula is:

Weight per meter (kg) = D² / 162

Where:

D = Diameter of the rebar in millimeters (mm)

162 = Constant derived from the density of steel (7850 kg/m³) and unit conversion factors

This formula provides a quick and reliable estimate for round, deformed, or plain rebar.

Step-by-Step Calculation Example
Let’s calculate the weight per meter for a 16 mm diameter rebar:

Identify the diameter (D): 16 mm

Apply the formula:
Weight = (16 × 16) / 162
Weight = 256 / 162 ≈ 1.58 kg/m

This means a 16 mm rebar weighs approximately 1.58 kilograms per meter.

Common Rebar Sizes and Their Weights
Here’s a quick reference for standard rebar sizes:

8 mm rebar: (8² / 162) = 0.395 kg/m

10 mm rebar: (10² / 162) = 0.617 kg/m

12 mm rebar: (12² / 162) = 0.888 kg/m

16 mm rebar: (16² / 162) = 1.58 kg/m

20 mm rebar: (20² / 162) = 2.47 kg/m

25 mm rebar: (25² / 162) = 3.85 kg/m

Why This Formula Works
The constant 162 is derived as follows:

Cross-sectional area of rebar = π × (D/2)²

Volume per meter = Area × 1 meter

Weight = Volume × Density of steel (7850 kg/m³)

Simplifying the equation: Weight = (D² / 162.2) ≈ D² / 162

This formula ensures accuracy while being easy to use on-site or during planning.

Practical Applications

Material Estimation: Calculate total rebar needed for slabs, beams, or columns.

Cost Calculation: Multiply weight by price per kg to budget accurately.

Logistics Planning: Determine transportation requirements based on total weight.

Factors to Consider

Rebar Type: Deformed or plain rebar—the formula applies to both.

Tolerances: Actual weight may vary slightly due to manufacturing standards.

Density: For specialized steels, adjust the constant if density differs from 7850 kg/m³.

Ruixiang Steel’s Support
As a reliable supplier, Ruixiang Steel offers:

Quality Rebar: Compliant with international standards (e.g., ASTM, BS, GB).

Technical Assistance: Help with calculations and project-specific needs.

Certified Products: Ensured consistency in dimensions and weight.

Conclusion
Using the formula Weight = D² / 162 simplifies rebar weight calculations, saving time and reducing errors. For accurate results, always pair this method with quality materials from trusted suppliers like Ruixiang Steel. Whether for small residential projects or large-scale infrastructure, this approach ensures efficiency and reliability in construction planning.