Structural Calculators
Check beams, LVL members, deck takeoffs, shafts and columns: wood spans, rafter geometry, deck board and footing-concrete quantities, area moment of inertia and section modulus S = I/c for common sections, LVL plies/depth/line loads, shaft torsion stress and angle of twist, beam load capacity, general beam deflection, solid shaft diameter from torque and bending, Euler column buckling, plus round-shaft and square-tube deflection checks.
Section Modulus
Area moment I, section modulus S = I/c, area and neutral axis for a rectangle, round, tube, I-beam, channel, tee or angle.
Shaft Diameter
Required solid shaft diameter from torque, bending moment, allowable shear and safety factor.
Shaft Torsion
Circular-shaft torsion stress, angle of twist, polar moment J and torque capacity.
Shaft Deflection
Bending deflection, stress and I for a round shaft as a beam (simply supported or cantilever).
Column Buckling
Euler critical load, effective length, slenderness and utilization for columns or cylinder rods.
Square Tube Deflection
Deflection, stress and I of a square/rectangular HSS tube used as a beam.
Beam Deflection
General beam deflection, bending moment and stress from I and S for common point and uniform load cases.
Beam Load Capacity
Allowable beam load from section modulus, span and allowable bending stress.
Wood Beam Span
Preliminary sawn-lumber beam or joist span from 2x size, spacing, live/dead loads and entered E, Fb and Fv values.
Deck Board
Decking board count, board rows, linear decking, fasteners and board cost from deck size and board layout.
Deck Footing Concrete
Concrete volume, bag count and concrete weight for round deck footings from diameter, depth and count.
Rafter
Common rafter length, roof rise, pitch angle, overhang tail length and rafter count for gable roof layout.
LVL Beam
Preliminary LVL beam sizing from span, plies, depth, uniform line loads and product design values, with bending, shear and deflection checks.
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These tools handle the questions every machine-frame, roof layout, deck takeoff, beam or shaft check comes down to: what is the geometry, how stiff is the section, will it stay below allowable stress, and will a compression member buckle first. The wood beam span calculator screens a single sawn rectangular member from 2x size, spacing, live/dead area loads and entered E, Fb and Fv values, then compares bending, shear, live-deflection and total-deflection span limits. The rafter calculator covers common gable-roof layout from span, pitch, ridge thickness, overhang and spacing, returning run, rise, cut length, pitch angle, rafter count and stock length. The deck board calculator is intentionally a material takeoff, estimating board rows, boards to buy, linear decking, screws and board cost from a rectangular layout. The deck footing concrete calculator estimates round-footing concrete volume, bags and weight from diameter, depth, count, bag yield and density. These deck tools do not size footings, joists, connections or code details; final framing still needs approved span tables or engineering.
The section modulus calculator returns the area moment of inertia I, the section modulus S = I/c, cross-section area and neutral-axis location for a solid rectangle, round bar, round or rectangular tube, plus I-beam, channel, tee and angle sections — the same I that feeds the bending-stress equation σ = M/S. The LVL beam calculator adds the practical engineered-wood layer: plies, depth, live/dead line loads, product E/Fb/Fv values, bending, shear and L/deflection checks. The beam load capacity calculator turns section modulus, span and allowable stress into total point or uniform load, while the beam deflection calculator uses entered I and S for simply supported and cantilever loads, returning deflection, maximum moment and bending stress. The shaft torsion calculator checks circular-shaft shear stress, angle of twist and polar moment J; the shaft diameter calculator solves solid round shaft diameter from torque, bending moment and allowable shear.
Pair those with the round-shaft deflection calculator for δ = F·L³/(48·E·I) simply supported or F·L³/(3·E·I) as a cantilever, or the square and rectangular tube deflection calculator for HSS members carrying a transverse load.
The column buckling calculator applies Euler Pcr = π²EI/(KL)² with effective length and slenderness. Every result shows the governing closed-form expression, in both metric and imperial, and the guide on what is section modulus explains the underlying geometry if S and I still feel abstract.