Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Deflection Millimeters (mm)

Required number input.

Span Millimeters (mm)

Required number input.

Allowable Deflection Millimeters (mm)

Required number input.

Compare measured beam deflection with a supplied project-specific allowable deflection; also report the deflection-to-span ratio. This does not determine the allowable limit. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Deflection To Span Ratio

The resulting deflection to span ratio returned as a number.

Within Limit

The resulting within limit returned as a boolean.

• Simple beam equations assume stated supports, loads, linear elasticity, small deflection, and an appropriate section property. Shear deformation, local buckling, lateral-torsional buckling, cracking, creep, connections, dynamics, and code combinations may govern.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Bolt Shear Capacity

  Nominal single-shear force from bolt shear area times a user-supplied allowable shear stress; not a code-rated connection capacity.

• Factor Of Safety

  Nominal strength-to-applied-demand ratio for quantities expressed in the same units; does not select an acceptable design margin.

• Ampacity Derated

  Adjusted current rating from a base ampacity times a supplied 0–1 derating factor; not a code sizing result.