Rebar Calculator
Rebar weight is calculated using the standard formula (diameter² / 162) x length, which gives weight in kilograms. This formula is widely used in construction for estimating steel reinforcement.
What Is Rebar?
Rebar weight is the mass of steel reinforcement bars needed for concrete, calculated using the formula (diameter² / 162) x length, giving weight in kilograms. The constant 162 converts mm² and meters into kilograms. Accurate rebar estimates ensure structural integrity without excess steel.
Example
Formula: (Diameter^2 / 162) x Length = (12 mm^2 / 162) x 50 m = 44.44 kg
Enter diameter and length in any unit, then the result will be in kg.
Tip: Choose your result unit on the right before calculating.
Step-by-step calculation
- Enter bar diameter and total length with units.
- Calculate to see rebar weight in kg.
How this is calculated
Reinforcement length is taken from the layout (slab or footing schedule); weight = total length times unit weight per meter (about d²/162 kg/m for metric bars). We add 3–5% for cut-offs and bends.
Sources: IS 1786 (Steel for Reinforcement of Concrete); SP 16 (Design Aids for RC).
FAQ
- How do I calculate rebar weight by hand?
- Use (diameter² / 162) x length. Example: (12² / 162) x 50 = 44.44 kg.
- What is the formula for rebar weight?
- Weight = (Diameter² / 162) x Length. Diameter in mm, length in meters, result in kg.
- Rebar vs steel bar weight
- Rebar is ribbed steel for concrete; the same formula applies to plain steel bars of the same diameter.
- What units should I use?
- Use mm for diameter, meters for length, and kg for result.
- Can I use this for mesh reinforcement?
- Yes. Enter total bar length for all bars in the mesh.