Free Online Truss Calculator
Analyse roof trusses, bridge trusses, and structural trusses with our free structural analysis tool. Get member forces, stress, reactions, and deflections in seconds. No signup or download required.
Draw your own geometry or use the structure wizard to generate common truss layouts
Truss Types You Can Analyse
AutoCalcs handles all common truss configurations. Whether you're designing a roof truss, checking a bridge structure, or analysing a custom truss geometry, get accurate results using finite element analysis.
Truss Configurations
- Roof trusses (pitched, flat)
- Warren, Pratt, Howe trusses
- Bridge trusses
- Custom truss geometries
Analysis Features
- Tension/compression-only members
- Pin-jointed analysis
- Self-weight calculation
- Multiple load combinations
Results
- Axial forces (tension/compression)
- Member internal forces
- Member stress contours
- Support reactions
- Deflected shape visualisation
Modelling Tools
- Structure wizard
- Draw freeform geometry
- Section library
- Member end releases (pin joints)
Pin-Jointed Truss Analysis
For true truss behaviour where members carry only axial forces, use member end releases to create pin connections at joints. This gives you the classic truss analysis results: pure tension and compression in each member.
AutoCalcs also supports rigid connections if you need to analyse trusses with moment-carrying joints or want to check secondary bending effects.
How It Works
AutoCalcs uses finite element analysis, not fixed textbook formulas, so you can solve roof trusses, bridge trusses, and custom layouts the same way you would in a full structural model.
- Build the geometry - Use the structure wizard for common layouts, or draw nodes and members freeform
- Set supports - Pin, roller, fixed, or custom restraints at the supports
- Assign sections and materials - Pick from the section library and material database
- Apply loads - Node loads, member loads, and self-weight; combine cases as needed
- Pin the joints if needed - Use member end releases for classic pin-jointed truss behaviour
- Run and inspect results - Axial forces, member stress, reactions, and deflected shape
Why Choose AutoCalcs for Truss Analysis?
- Instant Access - No installation. Start modelling in your browser immediately.
- Design Code Checks - Integrated AISC 360, Eurocode 3, AS 4100, and CSA S16 steel design checks (usage limits apply).
- 2D and 3D - Analyse planar trusses or space frames.
- Professional Accuracy - FEA-based solver using the Direct Stiffness Method.
- Open Source Engine - Powered by verified open-source FEA libraries.