Rebar Weight Calculator

Looking for a quick way to calculate the weight of steel rebars?
Our free Rebar Weight Calculator lets you find the weight per meter, per bar, and total weight instantly.
Enter your rebar diameter, length, and quantity — get accurate results with clear, step-by-step explanations.

System

Diameter

Length

Quantity (bars)

Density (steel)

kg/m³

Default 7850 kg/m³. Change if needed.

Weight per meter: — kg/m

Weight per bar: — kg

Total weight: — kg (— lb)

How this is calculated

We use the steel rod formula: weight_per_meter = π × (d/1000)^2 / 4 × density, where d is diameter in millimetres and density defaults to 7850 kg/m³.

Imperial inputs are converted: in → mm (× 25.4) and ft → m (× 0.3048). Total weight = weight per meter × length × quantity.

Rebar Weight Calculator

Compute rebar weight fast — includes both metric (mm, m) and imperial (in, ft) units with automatic conversion and formula breakdown.

Diameter
Length
Quantity
Density (kg/m³)
System (Metric / Imperial)
Demo Clear

Enter at least one valid diameter and length.

How It Works

The calculator uses the standard steel rebar formula:

Weight per meter = π × (d/1000)² / 4 × Density

Where:

d = bar diameter (mm)
Density = 7850 kg/m³ by default (for mild steel)
π ≈ 3.1416

For imperial units, the calculator automatically converts:

Inches → mm (× 25.4)
Feet → meters (× 0.3048)

It then multiplies the weight per meter by the bar length and quantity to show the total weight in kilograms and pounds.

Example

Example 1 – Metric:
Diameter = 16 mm Length = 12 m Quantity = 10

1️⃣ Weight per m = 1.579 kg
2️⃣ Weight per bar = 1.579 × 12 = 18.95 kg
3️⃣ Total = 18.95 × 10 = 189.5 kg (≈ 417 lb)

Example 2 – Imperial:
Diameter = 0.625 in Length = 40 ft Quantity = 5
The tool converts units automatically and shows results in both kg and lb.

Why Use This Calculator?

✔ Handles metric and imperial measurements
✔ Lets you customize steel density
✔ Supports quick diameter presets (Ø8 – Ø32 mm)
✔ Displays step-by-step calculations
✔ Mobile-friendly and SEO-optimized
✔ Free, fast, and ad-free

Common Rebar Sizes and Weights

Diameter (mm)	Weight per m (kg/m)	Typical Use
8 mm	0.395	Light slabs, driveways
10 mm	0.617	Beams, small columns
12 mm	0.888	Standard columns
16 mm	1.579	Footings, heavy slabs
20 mm	2.466	High-load beams
25 mm	3.854	Foundation mats
32 mm	6.313	Large structures / bridges

How to Use the Rebar Weight Calculator

1️⃣ Select unit system (Metric or Imperial)
2️⃣ Enter the diameter, length, and quantity of rebars
3️⃣ (Optionally) adjust the steel density (default = 7850 kg/m³)
4️⃣ Click Calculate to see:
– Weight per meter
– Weight per bar
– Total weight (kg and lb)

FAQ

Q: What does this calculator do?
It calculates the total weight of reinforcing steel bars (rebars) used in concrete structures.

Q: Can I use inches and feet?
Yes — switch to the Imperial system. The tool automatically converts inches → millimetres and feet → metres.

Q: What is the default steel density?
7850 kg/m³, which is standard for mild steel. You can adjust it for stainless or high-tensile steel.

Q: Why is rebar weight important?
Knowing the total steel weight helps estimate cost, transport needs, and structural load accurately.

Q: Does the calculator work on mobile?
Yes — it’s responsive and optimized for smartphones and tablets.

Formula Reference

Weight (kg) = π × (Diameter / 1000)² / 4 × Density × Length × Quantity

Imperial values are first converted to metric for accurate results.

Real-Life Uses

Construction site planning and procurement
Material cost estimation
Structural and civil engineering design
Shipping and logistics calculations
Academic and training projects