Free Tool

Press Brake Tonnage Calculator

Air-bending tonnage formula: T (t/m) = (t² × Rm) / (8 × V). Enter your parameters below — includes 20% safety margin.

Material Tensile strength (Rm) is pre-filled for common grades

Tensile Strength Rm (MPa) Find Rm on your material certificate

Material Thickness (mm)

Bend Length (mm)

V-Die Opening (mm) Standard rule: V = 8 × thickness

Auto-fill V-die opening as 8 × thickness when thickness changes

Required Tonnage (with 20% safety margin)

—t

Safe Machine Capacity

—

Tonnage per Metre

—

Material

—

Tensile Strength

—

Formula: T = (—) × 1.20 safety margin

How the Calculator Works

This calculator uses the standard air-bending tonnage formula:

T (t/m) = (t² × Rm) / (8 × V)

Where t = material thickness (mm), Rm = tensile strength (MPa), and V = V-die opening (mm). The result is multiplied by bend length and a 20% safety margin.

For a full explanation including a mild steel reference chart and material tensile strength table, see Press Brake Tonnage Calculation: Complete Guide.

Related Resources

Tonnage Calculation Guide Hydraulic vs Electric Press Brakes Bend Allowance Guide Chip-Thinning Calculator