AutoEngCalc - Engineering Calculators

Nut-Bolt Tensile Strength

Calculate proof load, yield strength, ultimate tensile load and safe clamp force for metric and inch bolts. Includes all common grades with preload safety factor.

Proof Load
163 kN
M16 Grade 12.9 • 75% Preload = 122 kN

Bolt Tensile Strength

Featured: Proof Load, Yield, Ultimate • Preload Safety

Tensile Load Capacity by Grade

Proof, Yield & Ultimate loads for selected size

Metric Grades (ISO 898-1)

Proof Load = Stress Area × Proof Stress

Inch Grades (SAE J429 / ASTM)

Proof Load based on minimum tensile strength

Select bolt parameters to see results

Bolt Grade Reference

Metric ISO Grades

  • 8.8: Proof 600 MPa, Tensile 830 MPa
  • 10.9: Proof 830 MPa, Tensile 1040 MPa
  • 12.9: Proof 970 MPa, Tensile 1220 MPa

Inch SAE/ASTM

  • Grade 5: Proof ~85 ksi, Tensile 120 ksi
  • Grade 8: Proof ~120 ksi, Tensile 150 ksi
  • A325: Structural, Proof 85–120 ksi
Footer - AutoEngCalc