Hydraulic Cylinder Force Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
Enter Values
How to use this calculator
- Enter the system pressure in bar and the cylinder bore diameter in mm.
- Optionally add the rod diameter to also get the retract (pull) force.
- Read the extend and retract forces in kN.
How it works
The Hydraulic Cylinder Force Calculator finds the push and pull force a cylinder produces from pressure and piston area.
Force = pressure × area. The extend (push) stroke uses the full bore area π·D²/4; the retract (pull) stroke uses the annulus area (bore minus rod), so it produces less force. With pressure in bar (0.1 N/mm²) and area in mm², force(kN) = pressure × area ÷ 10,000.
Worked example
150 bar, 50 mm bore. Bore area = π×50²/4 = 1963 mm². Extend force = 150 × 1963 ÷ 10,000 ≈ 29.5 kN.
Frequently asked questions
Why is the retract force lower?
On retract, oil pushes on the annulus (the bore area minus the rod area), which is smaller than the full bore, so the same pressure gives less force.
Does this account for friction or back-pressure?
No — it is the theoretical force from pressure × area. Real output is a little lower due to seal friction and back-pressure on the return line.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.