Updated Concrete & Structure

Concrete Beam Calculator

Estimate concrete beam capacity, allowable load, material quantities, reinforcement lengths, stirrup counts and steel weight with this multi-mode concrete beam calculator.

Flexural Capacity & Load Concrete Volume & Formwork Rebar & Stirrup Quantities

Concrete Beam Capacity, Load & Rebar Estimator

Span and member dimensions are entered in feet and inches or metres and millimetres.
Beam width and depth use these units in every mode.
Concrete strength f'c and steel yield strength fy use this unit system.
Inches or millimetres depending on the section units above.
From extreme compression fibre to bottom of beam.
psi or MPa according to the strength units setting.
Typical reinforcing steel is 60,000 psi or 415 MPa.
Effective depth d is taken as this factor × overall depth (typical range 0.85–0.92).
Enter factored design moment at the critical section for a capacity check.