Free online FEM calculator with Eurocode design checks

EN 1990 · EN 1992 · EN 1993 · EN 1995 · EN 1998

A complete 3D frame analysis, in the browser

The solver is a full 3D finite-element frame analysis: 12-degree-of-freedom beam elements with end releases, rigid eccentric offsets, elastic (spring) supports and support settlement. Everything runs client-side, so there is nothing to install and nothing to upload.

• Nodal and member loads: uniform, trapezoidal and partial distributed loads, point forces and moments, temperature loads, in local or global axes, plus automatic self-weight — and snow, wind and icing load calculators
• Load cases with Eurocode action types, EN 1990 ULS/SLS combination generator with editable partial and combination factors, and envelopes as first-class objects
• Nonlinear analysis: tension-only and compression-only bars, one-way supports with gaps, two-sided slots, bilinear springs, measured force–displacement curves and one-way end releases — solved by an active-set iteration that reports what lifted off and what went slack
• Stability: second-order P-Delta analysis, the critical load factor α_cr of every load case and combination with the EN 1993-1-1 §5.2.1 verdict, buckling mode shapes, buckling lengths suggested from the modes, and EN 1993-1-1 §5.3.2 imperfections
• Dynamics: natural frequencies and mode shapes, EN 1998-1 response spectrum with equivalent seismic load cases, and floor vibration screening
• Results: deflected shape, internal-force diagrams (N, V, M), reactions, envelope min/max bands, and an independent solution check (equilibrium, energy, active-set consistency)

Eurocode design checks — not just analysis

Most free online calculators stop at internal forces. This one carries on to the design check, which is the part that actually takes your time.

• Timber — EN 1995-1-1 (Eurocode 5): cross-section checks and stability (flexural buckling 6.3.2, lateral-torsional buckling 6.3.3) with k_mod, γ_M and k_def, spaced (twin) columns to Annex C, serviceability deflection (w_inst, w_fin), dowel-type connections to §8 and fire design to EN 1995-1-2
• Steel — EN 1993-1-1 (Eurocode 3): cross-section classification (Class 1–4 with EN 1993-1-5 effective sections), §6.2 cross-section resistances, and §6.3 flexural, torsional-flexural and lateral-torsional buckling — angles and tees included — with a searchable library of 2457 profiles from eleven standards (EN, British, American, Japanese, Chinese, Russian, Indian and Australian), plus welded girders and cold-formed purlins
• Concrete — EN 1992-1-1 (Eurocode 2): reinforcement design (longitudinal bars, side bars and links, with support zones), M-N interaction for rectangular and circular sections, shear, §5.8 column slenderness, cover to the exposure class, and serviceability — stress limits, crack width and long-term deflection with creep and shrinkage
• Every assessment produces a printable A4 report you can hand to a checking engineer

Cross-section calculator — properties of any shape

A second, standalone tool for the sections no catalogue carries. Draw any cross-section — polygons, rectangles, circles and holes, catalogue profiles from the same library of 2457 sections, or thin-walled walls as a mid-line with a thickness — and every property is computed as you draw. Open the cross-section calculator

• Exact outline integrals: area, centroid, second moments and product of inertia, principal axes, radii of gyration, elastic moduli at every extreme fibre, and plastic moduli about y, z, u and v
• Finite elements on the section itself: the St Venant torsion constant I_t, the warping constant I_w, the shear centre and the shear areas, for any shape — solid, open, closed or with several cells
• Thin-walled mode with the mid-line theory beside the finite-element values, mass per metre, paint perimeter, units in mm or cm, and the table copied to Excel or saved as CSV

Why engineers use it

• Free and instant — open a browser tab and model. No licence, no install, no account.
• Private by design — the whole solver runs on your machine. Your model is never uploaded to any server.
• Seven languages — English, Czech, Slovak, Polish, German, French and Spanish.
• Real workflow — DXF import, JSON save/load, CSV and clipboard export of result tables, printable reports.

Who it is for

Structural engineers doing quick frame and roof checks, timber designers sizing purlins and rafters, steel detailers verifying a portal frame, and civil-engineering students learning how frame analysis and Eurocode design fit together. If you need a fast, trustworthy answer without booting up a heavyweight package, this is built for you.

Verification examples

Every result the solver produces is checked against an independent reference — a closed-form hand calculation or a classical method — not just against itself. A few worked examples, as PDF reports:

• Three-hinged portal frame — reactions and bending moments match a hand statics solution to floating-point precision. View PDF
• King-post roof truss — every member axial force, including a zero-force member, matches an exact method-of-joints solution. View PDF
• Simply supported beam under a distributed load — reactions, shear, moment and deflection all match the classical Euler-Bernoulli solution. View PDF
• Beam with a rotational end spring — spring moment, reactions, deflection and end rotations match the closed-form force-method solution for any spring stiffness, from a pin to full fixity. View PDF
• Cantilever column, second-order analysis — linear results match the cantilever formulas exactly; the P-Δ results and the critical load factor match the exact beam-column solution, converging as the column is meshed finer. View PDF
• Natural frequencies of a simply supported beam — the modal analysis reproduces the exact solution of its lumped-mass model to round-off with both eigensolvers: frequencies, mode order in all three directions (strong axis, weak axis, axial) and effective masses; against the continuous Euler-Bernoulli beam the first frequency is within 4·10⁻⁷ on 20 members, converging as h⁴. View PDF
• Euler buckling of columns with four support conditions — the linear buckling analysis reproduces Euler’s critical loads for fixed–free, pinned–pinned, fixed–pinned and fixed–fixed columns — first and second modes in both bending planes, in the correct order with no repeated factor skipped — together with the buckled shapes and buckling lengths; with 10 members the governing α_cr is within 10⁻⁶, converging as h⁴ and holding on meshes of up to 1 000 members. View PDF
• Linear time history of a single oscillator — a cantilever with a mass at its top, released, struck by a sudden load, driven harmonically and shaken by its base: modal superposition matches the closed-form response to round-off, Newmark integration matches its own recurrence worked by hand to round-off, base shear with the damper force included, and both converge to the exact solution as Δt². View PDF
• Response spectrum analysis of a two-mass cantilever — periods, participation factors and effective masses with all four eigensolvers, the EN 1998-1 design-spectrum ordinates, modal base shears, the exported equivalent static forces and the static results of each mode and of their SRSS combination match the exact solution of the two-degree-of-freedom system to round-off. View PDF
• X-braced bay with tension-only diagonals — the nonlinear solver finds the active rod for either load direction; reactions, member forces and deflections match the method of joints and the force method exactly, and combinations are solved on their total load. View PDF
• Timber beam in bending (EC5) — a laterally unrestrained C24 beam: k_mod, design strengths, bending, shear and lateral-torsional buckling utilizations match an EN 1995-1-1 hand calculation. View PDF
• Timber column, buckling about both axes (EC5) — a glulam column with different buckling lengths about y and z: slenderness, k_c and the buckling interactions (6.23/6.24) with bending match an EN 1995-1-1 hand calculation. View PDF
• Steel beam, lateral-torsional buckling (EC3) — a fork-supported IPE 300 under a uniform load on the top flange: C₁ from the moment diagram, the load-height term, M_cr, χ_LT,mod and M_b,Rd match an EN 1993-1-1 hand calculation, with the load on the top flange and at the shear centre. View PDF
• Steel columns, buckling in class 3 and class 4 (EC3) — two S355 hollow-section columns on either side of the class 3/4 limit: classification, the effective width of each wall (EN 1993-1-5), A_eff, slenderness and N_b,Rd match an EN 1993-1-1 hand calculation. View PDF
• Steel angle strut, flexural-torsional buckling (EC3) — two struts of an equal angle L 100×100×10, S235, 0.8 m and 2.5 m long: principal axes u and v, the shear centre, N_cr,T and the coupled N_cr,TF of 6.3.1.4 match an EN 1993-1-1 hand calculation; flexural-torsional buckling governs the short strut, flexure about v the long one. View PDF

Frequently asked questions