Simple Beam Deflection Calculator (Point Load, Center)
Estimate deflection at the midspan of a simply-supported beam with a centred point load. Educational use — not for design.
About this calculator
The Simple Beam Deflection Calculator (Point Load, Center) on NumberCals is a free, mobile-friendly tool for anyone needing to estimate deflection at the midspan of a simply-supported beam with a centred point load. educational use — not for design. Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.
Formula used
δ = P·L³ / (48·E·I)
What you'll need
- Point Load P (N) (e.g. 5000)
- Beam Length L (m) (e.g. 4)
- Elastic Modulus E (Pa) (e.g. 200e9)
- Moment of Inertia I (m⁴) (e.g. 8.33e-6)
What you'll get
- Deflection at Centre (m)
- Deflection (mm)
Frequently Asked Questions
Typical E values? +
Steel: ~200 GPa (200×10⁹ Pa). Aluminum: ~70 GPa. Concrete: ~25–35 GPa. Pine timber: ~9 GPa. Always check material datasheets for your specific grade.
What does this NOT account for? +
Self-weight, distributed loads, end conditions other than simply-supported, dynamic effects, material non-linearity, large deformations, buckling. Real beams need full structural analysis.
Is this safe to use for design? +
No. For design, use full structural analysis software or work with a licensed structural engineer.