Hydraulic & Pneumatic Cylinder Calculator
Push and pull force, speeds, cycle time and power, and an air cylinder’s free-air use.
Try before you buy.
- Free preview: your inputs, the checks, the bores of the table’s first rows and a watermarked drawing, with the forces, pressures, speeds, air use and every figure hidden.
- Locked until you unlock it: download and copy.
- Unlock: Pro pass, ₹179 for 30 days or ₹79 for 1 week, a one-time payment that never renews. Unlock: Pro pass, $5.99 for 30 days or $2.99 for 1 week, a one-time payment that never renews.
Ways to unlock shows how to get the full result.
Printing this result is locked in the free preview.
Result
How it was worked out
Locked in the free preview. Opens the ways to unlock this result.
Locked in the free preview. Batch runs unlock with a pass.
Locked in the free preview. Query results unlock with a pass.
Results are estimates from the formulas shown, not a professional design or certification. Have a qualified engineer verify anything safety-critical (structures, electrical installations, gas or pressure systems).
About the Hydraulic & Pneumatic Cylinder Calculator
Size a hydraulic or pneumatic cylinder. For a hydraulic cylinder enter the bore, the rod and the pressure to get the push and pull forces — or the force you need to get the pressure — and the pump flow (or the extend speed you want) to get both speeds, the extend, retract and cycle times, the oil each stroke takes and the flow out of the other port, and the hydraulic power p·Q with the pump’s input power. A regenerative extension option shows the faster, weaker stroke when the rod-end oil joins the pump flow. A table compares the push and pull forces and speeds of the standard bores from 8 to 320 mm at your pressure.
For a pneumatic cylinder enter the bore, rod, supply pressure, stroke and cycle rate: you get the forces of a double-acting or a spring-return cylinder and the air it uses per cycle and per minute as a free-air volume: litres at the ISO 8778 standard reference atmosphere (ANR), normal litres (DIN 1343) and SCFM, with the tubes to the valve if you give them. Results are estimates for sizing and checking, not a professional design.
Without a pass, the free preview shows your inputs, the checks, the bores of the table’s first rows and a watermarked drawing of the cylinder; the forces, pressures, speeds, air use, the working, Copy result and the CSV come with a Pro pass.
How to use it
- Choose Hydraulic or Pneumatic, and metric or US units (switching converts what you have typed).
- Enter the bore and the rod diameter. For a hydraulic cylinder choose whether to work out the forces from a pressure or the pressure for a force, and give the pump flow or the extend speed you want.
- Add the stroke for the times and volumes, an efficiency if you know it, and optionally the pump’s efficiency and the cylinder’s rated pressure. For a pneumatic cylinder, add the cycles per minute, the tubes to the valve and the local air conditions.
- Read the forces, speeds, times and power or the air consumption, the checks and the bore table.
- Copy the result or download it as a CSV — with a Pro pass, or after unlocking this result.
Examples
Stroke 500 mm, 100 % efficiency
Push 80.42 kN, pull 54.98 kN; out at 0.133 m/s in 3.77 s, back at 0.194 m/s in 2.58 s (9.45 cycles a minute); 58.5 L/min leaves the cap end while retracting; hydraulic power 10.67 kW; a blocked rod port while extending can reach 234 bar
The same cylinder at 95 % efficiency
p = 50 kN ÷ (5,026.5 mm² × 0.95) = 104.7 bar
The same cylinder and pump, rod-end oil fed back
Out at 0.419 m/s (Q ÷ rod area) with 25.45 kN, instead of 0.133 m/s with 80.42 kN
100 mm stroke, double-acting, 10 cycles a minute, 20 °C, sea level
Push 1,178 N, pull 990 N; filling 0.361 L of cylinder volume each cycle takes 2.53 L of free-air volume: 25.3 L/min (ANR), 23.3 Nl/min or 0.870 SCFM
Common uses
- Choosing a bore and a working pressure for a press, a clamp, a tipper or a lifting cylinder
- Working out the pump flow for a required cylinder speed, and the cycle time it gives
- Sizing the return line and valve for the extra flow from the cap end
- Estimating the compressed air a pneumatic machine uses, for the compressor and the running cost
- Hydraulics and pneumatics coursework, with the working shown
Formulas
- Areas: piston A₁ = πD²/4, annulus A₂ = π(D² − d²)/4, rod A_r = πd²/4; area ratio φ = A₁/A₂
- Forces: F_push = p A₁ η, F_pull = p A₂ η; regenerative extension F = p A_r η
- Pressure for a force: p = F ÷ (A η)
- Speeds: v_out = Q ÷ A₁ (Q ÷ A_r regenerative), v_in = Q ÷ A₂; the flow leaving the other port is v times its area, so a retracting cylinder pushes Q × φ out of its cap end
- Times: t = S ÷ v each way, plus any dwell; cycles a minute = 60 ÷ cycle time
- Power: P = p Q (hydraulic), and P ÷ η_pump for the pump’s input
- Intensification: with the rod port blocked or metered while extending, p_rod = p φ
- Free-air volume (isothermal): V_ref = (V_cyl (p_gauge + p_atm) + V_tubes p_gauge) ÷ p_ref × T_ref ÷ T: each chamber fills from empty to the supply pressure, while a tube, exhausted to atmosphere at the end of each stroke, takes only its volume times the gauge pressure
Free-air reference states
- ANR, ISO 8778: 100 kPa, 20 °C and 65 % relative humidity, the standard reference atmosphere for pneumatic components
- Normal litres, DIN 1343: 101.325 kPa and 0 °C
- SCFM: cubic feet a minute at 14.696 psia and 60 °F here; American catalogues also use 68 °F, a few per cent different, so check which one a data sheet means
The air is treated as dry; the humidity in the ISO 8778 definition changes the figure very little.
Sources
- ISO 3320: cylinder bores and piston rod diameters, metric series (the bore table)
- ISO 8778: pneumatic fluid power, standard reference atmosphere
- DIN 1343: reference state, normal conditions and normal volume
- ISO 4413 and ISO 4414: general rules and safety requirements for hydraulic and pneumatic systems
Limitations
- Steady speeds: the acceleration, cushioning at the ends of the stroke and the time valves take to switch are not included.
- Pressure losses in hoses, valves and fittings lower the pressure at the cylinder; enter the pressure at the port, not at the pump.
- No rod buckling, seal speed limit or mounting check: long strokes in compression need a column check of the rod, and the maker’s limits apply.
- The free-air figures assume the cylinder fills to the supply pressure each stroke and exhausts to atmosphere, and leave out the small dead volume at the ends of the stroke.
- An estimate for sizing and checking — not a professional design. Hydraulic systems store a lot of energy: follow ISO 4413 or ISO 4414 and the maker’s ratings.
Privacy
On this device: nothing is sent
Everything happens in your browser. What you enter or open here is not uploaded or stored by MySmartCoPilot.
Frequently asked questions
What do I get without a pass?
Without a pass, Hydraulic & Pneumatic Cylinder Calculator shows your inputs, the checks, the bores of the table’s first rows and a watermarked drawing, with the forces, pressures, speeds, air use and every figure hidden. Until you unlock it, the result can’t be downloaded or copied. A Pro, Premium or Ultimate pass, a one-time payment that never renews, unlocks the full result. The pricing page lists the passes and their prices.
How do I calculate the force of a hydraulic cylinder?
Force = pressure × area. Pushing, the area is the full piston, πD²/4; pulling, it is the annulus π(D² − d²)/4. An 80 mm bore at 160 bar pushes 160 × 10⁵ Pa × 0.005027 m² = 80.4 kN; with a 45 mm rod it pulls 55.0 kN. Seal friction lowers both a little.
How fast will my cylinder move?
Speed = flow ÷ area. 40 L/min into an 80 mm bore moves the piston out at 0.667 L/s ÷ 5,027 mm² = 0.133 m/s, and back faster, at 0.194 m/s, because the annulus is smaller.
Why does more oil come out of the cap end than the pump supplies?
While retracting, the pump fills the annulus, but the piston pushes the whole cap-end volume out — the flow times the area ratio φ = A₁/A₂. With φ = 1.46, 40 L/min in gives 58.5 L/min out, so the return line, valve and filter must be sized for it.
What is pressure intensification?
If the rod-end port is blocked, or the outflow is metered, while the cylinder extends, the full force on the piston has to be held by the smaller annulus, so the rod-end pressure rises to p × A₁/A₂ — 234 bar from 160 bar in the example. Rod-end seals, hoses and relief valves must be rated for it.
What is the difference between L/min (ANR), Nl/min and SCFM?
All three are free-air flows, the volume the air would take at a stated reference state: ANR at 100 kPa and 20 °C (ISO 8778), normal litres at 101.325 kPa and 0 °C (DIN 1343), and SCFM in cubic feet at 14.696 psia and 60 °F here. Because the reference temperatures differ, one flow gives three different numbers.