About this app
Timber Engineering Calculator — 55 calculators for timber and wood-works design. Available in Metric (SI) and Imperial (USCS) units. NEW — Wood Species Reference & Auto-Fill: • Built-in species library (NDS 2018): Douglas Fir-Larch, Southern Pine, Hem-Fir, Spruce-Pine-Fir — Select Structural, No.1, No.2 • View Fb, Ft, Fv, Fc⊥, Fc, E and G in SI (MPa) and USCS (psi) • One-tap auto-fill of design values into calculators — faster, fewer errors • Auto-fillable fields marked with a tree icon Save calculations to History, add notes, export PDF reports. Formula shown on top; Calculate activates when all inputs are entered. SECTION PROPERTIES • Area of Section • Moment of Inertia • Distance from Axis to Extremities • Radius of Gyration • Section Modulus BENDING & SHEAR • Maximum Fiber Stress • Maximum Fiber Stress using Section Modulus • Horizontal Shearing Stress • Horizontal Shearing Stress (notched beam) • Modified Total End Shear (Concentrated / Uniform Loads) TIMBER COLUMNS (species auto-fill) • Allowable Unit Stress — Single/Glued, Rectangular, Circular • Allowable Compressive Stress at an angle to grain • Allowable Stress — Rectangular (NDS) • Hankinson's Equation ADJUSTED DESIGN VALUES (species auto-fill) • Extreme-Fiber Bending, Tension, Shear • Compression perpendicular / parallel to grain • End grain in bearing • Modulus of Elasticity DESIGN FACTORS • Size Factor • Volume Factor (Southern Pine / Other Species) • Radial Stress from Bending Moment • Curvature Factor • Bearing Area Factor • Slenderness Ratio for Beams NAILS & SPIKES • Allowable Withdrawal Load • Total Allowable Lateral Load — Group I–IV Wood WOOD SCREWS • Allowable Withdrawal Load • Total Allowable Lateral Load — Group I–IV Wood CONNECTORS — ADJUSTED DESIGN VALUES • Bolts — Lateral Loading • Split-Ring & Shear-Plate — Parallel / Normal to Grain • Nails & Spikes — Withdrawal / Lateral • Wood Screws — Withdrawal / Lateral • Lag Screws — Withdrawal / Lateral • Metal Plate Connectors — Lateral • Drift Bolts & Pins — Withdrawal / Lateral • Spike Grids — Lateral • Stress and Deflection Factor (Ponding) Also available: Civil Engineering Pack — 12 modules (Beam, Structural, Concrete, Column, Hydraulics, Survey, Soil, Piling, Highways, Bridge, Converter) in SI and USCS.
Latest release
What’s New
• NEW: Built-in Wood Species Reference (NDS 2018) • One-tap auto-fill of design values into calculators
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- First observed Aug 10, 2026 · 3:33 PM $3.99