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.
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