Beam Deflection Calculator
Enter SI values for P, L, E, and I to calculate the center deflection and, when defined, L/δ.
A QUICK WALKTHROUGH
How to use this tool
- Enter center load P in newtons and beam span L in metres.
- Enter Young’s modulus E in pascals and second moment of area I in m⁴.
- Review the formula result; a zero load has zero deflection and no ratio.
Defined scope
Educational linear-elastic small-deflection model for a simply supported, constant-section beam with a center point load only. Results are formula outputs, not structural or safety advice.
Formula
Center deflection is δ = PL³/(48EI). The dimensionless span-to-deflection ratio is L/δ only when δ is greater than 0.
Local calculation
Inputs stay in this browser and are not uploaded or stored.
GOOD TO KNOW
Common questions
Which beam case is modeled?
A simply supported, constant-section beam with one center point load in a linear-elastic small-deflection model.
What happens when P is zero?
Deflection is zero and L/δ is undefined.
Does this assess structural safety?
No. It is an educational formula calculator and does not provide safety or compliance conclusions.