Pneumatic Cylinder Force Calculator
The force a pneumatic cylinder delivers on the push and pull strokes at a given air pressure — from the bore and rod diameters — with the air consumed per cycle, the consumption at a cycle rate, and the bore needed for a target force.
Force is pressure times piston area.
How the pneumatic cylinder force calculator works
Force is pressure times piston area. On the push stroke the whole bore works; on the pull stroke the rod takes up part of the area, so the pull force is less. Real cylinders lose 10 to 15% to seal friction, which the efficiency input covers. Air consumption per cycle is the swept volume of both strokes, scaled up to free air by the pressure ratio — the number that sizes the compressor.
Formula: F_push = P × π D²/4 × η; F_pull = P × π (D² − d²)/4 × η; free air per cycle = swept volume × (P + P_atm) / P_atm
Worked examples
| Inputs | Push force (N) | Note |
|---|---|---|
| A 63 mm cylinder at 6 bar | 1,645.9 | about 1,650 N push |
| Higher pressure | 2,194.5 | a third more force |
| A big rod | 1,645.9 | a weaker pull stroke |
FAQFrequently asked questions
How is cylinder force calculated?
Pressure times the piston area the air acts on: the full bore when pushing, the bore less the rod when pulling. Gauge pressure in pascals times area in square metres gives newtons.
Why is the pull force lower?
Because the rod occupies part of the piston face on that side, so the air has less area to push against. A thick rod for a long stroke makes the difference large.
What efficiency should I use?
Eighty-five to ninety per cent for a standard seal-friction loss; less for old or dry cylinders. Size for the load with a margin on top of that — 50% is common for reliable operation.
Why does air consumption matter?
Compressed air is expensive — roughly ten times the cost of the same energy as electricity. The free-air figure sizes the compressor and prices the machine's running cost.
What are standard bores?
ISO sizes run 8, 10, 12, 16, 20, 25, 32, 40, 50, 63, 80, 100, 125, 160, 200, 250, 320 mm. Choose the next size up from the calculated bore.
Where these figures come from
- NIST — CODATA 2018 fundamental physical constants — G, g₀, R, c
- NIST Special Publication 811 — Guide for the use of the International System of Units — unit conversions
- The Engineering ToolBox — material properties — specific heats, expansion coefficients, densities
- National Physical Laboratory — the UK's national measurement institute
Last checked: September 2026. Constants are the CODATA 2018 values; formulas are the standard textbook forms.