Calculator
Wood beam calculator
Size wood beams and joists with the timber material preset (E = 13 GPa) and a rectangular section matching your nominal lumber size. The deflection badges check the L/240 and L/360 limits commonly used for floors and roofs. The calculator below is pre-loaded; change anything and results update instantly.
About this case
Classic textbook case: uniform load over the whole span.
All diagrams use the Euler–Bernoulli beam theory with an exact finite-element solver that runs entirely in your browser. You can move supports by dragging them, switch unit systems at the top of the input panel, and export results as CSV or a printable report.