Hydraulic Cylinder Force Calculator

Formula

• F = P × A
• A_bore = π/4 × D_bore²
• A_retract = π/4 × (D_bore² − D_rod²)

About this calculator

Part of our Fluid Power Calculators collection. Pneumatic and hydraulic cylinder forces and system sizing.

How it works

Hydraulic extend and retract forces use the same area logic as pneumatic cylinders, but at typical hydraulic pressures. Extend uses full piston area. Retract subtracts the rod area from the bore.

Enter your values in the inputs above and click CALCULATE. Results appear on the right without a page reload. No login and no server upload.

Worked example

160 bar system pressure, 80 mm bore, 40 mm rod.

1. P = 160 bar = 16,000,000 Pa
2. Extend area = π/4 × 0.08² = 0.005027 m²
3. F_extend = 16,000,000 × 0.005027 = 80.4 kN
4. Retract area = π/4 × (0.08² − 0.04²) = 0.003770 m² → 60.3 kN

Result: Extend 80.4 kN, retract 60.3 kN, ratio 0.75.

When to use

• Checking cylinder force against a press or lift load
• Comparing extend vs retract capability on a double-acting cylinder
• Quick verification before selecting a standard bore

Limitations

• Static hydraulic force; no dynamic pressure drop or cushion effects
• Assumes full system pressure available at the port
• Does not check rod buckling or mount strength

FAQ

How is this different from the pneumatic calculator?

Same physics, different typical pressures. Hydraulics run 100 to 350 bar; pneumatics run 4 to 10 bar. This tool shows kN and N outputs.

What rod-to-bore ratio is typical?

Many standard cylinders use rod diameter about 50 to 65% of bore. Larger rods increase retract force but reduce extend area efficiency.

Does this include pressure drop in hoses?

No. Use the pressure measured or expected at the cylinder port, not pump relief setting alone.