Hydraulic Cylinder Force Calculator
Hydraulic cylinders convert fluid pressure into linear mechanical force, and how much force one produces depends entirely on its geometry and the system pressure driving it. This calculator works out both the extension (push) force and the retraction (pull) force a hydraulic cylinder generates. You enter the bore diameter and rod diameter in millimetres, choose a pressure unit (bar, MPa, PSI or kPa), and enter the system pressure. It returns extension and retraction force in newtons, kilonewtons and metric tonnes, plus a summary of the bore area, the annular (rod-side) area, the pressure converted to megapascals, and the rod-to-bore ratio as a percentage. A detailed breakdown shows the working for each stroke, since extension force uses the full bore area while retraction force uses the smaller annular area left once the rod is subtracted, which is why pull force is always lower than push force at the same pressure. Use it to check whether a cylinder can deliver the force your application needs, whether you are sizing a ram for a press, checking an excavator or loader arm, or specifying a cylinder for a trailer hoist. These are theoretical results based on gauge pressure and cylinder geometry only; actual output will be slightly lower in practice due to seal friction, fluid viscosity losses and back-pressure, so apply a safety factor and confirm critical designs with a qualified hydraulic engineer.
1. Cylinder Dimensions
2. Results Summary
Extension Stroke (push)
Retraction Stroke (pull)
Extension area = π x (0.050 m)² = 0.007854 m². Extension force = 20,000,000 Pa x 0.007854 m² = 157.08 kN (16.02 t).
Annular area = π x ((0.050)² − (0.035)²) = π x 0.001275 m² = 0.004006 m². Retraction force = 20,000,000 x 0.004006 = 80.11 kN (8.17 t).