Bolt Torque Calculator

Calculate bolt tightening torque from target axial force and friction coefficient online. Includes M6–M30 presets and bearing surface pressure — free engineering tool

Select Bolt Size

Nominal Dia.: 12 mm | Pitch: 1.75 mm

Stress Area: 84.3 mm² | Across Flats: 18 mm

Calculation Mode

T = K · d · F

Target Axial Force F (N)

Torque Coefficient K

Typical: 0.15-0.25

Results

Tightening Torque T

48.00 N·m

= 4.89 kgf·m

Bolt Stress

237.2 MPa

Bearing Surface Pressure

164.3 MPa

Bearing area: 121.7 mm²