About this calculator

Steel rebar weight per metre is (diameter² × π/4 × 7850) kg/m³. The calculator returns total weight from diameter, length and number of bars.

How it works

Enter your bar diameter (mm), bar length (m) and number of bars. The result updates as you type, using the formula shown below. Nothing you enter is stored.

Limits

Quantities assume regular shapes and standard waste allowances. Structural work still needs an engineer and Building Regulations sign-off.

Who it's for

DIY builders, site managers and tradespeople ordering materials or checking a take-off.

Formula: Weight = (π/4 × d² × L × ρ) × N, ρ = 7850 kg/m³

Frequently asked questions

What does the Rebar Weight Calculator do?

Calculate the weight of reinforcing steel bar from diameter and length. Steel rebar weight per metre is (diameter² × π/4 × 7850) kg/m³. The calculator returns total weight from diameter, length and number of bars.

Is the Rebar Weight Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Rebar Weight Calculator?

Results are calculated in real time using the formula Weight = (π/4 × d² × L × ρ) × N, ρ = 7850 kg/m³. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified construction & building professional before committing to a purchase or a job.

What inputs does the Rebar Weight Calculator need?

Enter values for: Bar diameter (mm), Bar length (m), Number of bars. Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Rebar Weight Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.