Pneumatic Cylinder Force Calculator #

Calculate push/pull force, minimum bore size, air consumption per cycle, and piston speed for single-acting and double-acting pneumatic cylinders. Supports metric (mm/bar/N) and imperial (inch/PSI/lbf) units, with standard bore selection per ISO 6432 / NFPA.

Input Parameters

Calculation Mode

Unit System

Bore Diameter (mm)

Required Force (N)

Stroke Length (mm)

Supply Pressure (bar)

Advanced calculator

Rod size, load factor, available flow, cycle rate, and cylinder action refine force and air use.

Rod Diameter (mm) Enter 0 for single-acting or rodless cylinders

Load Factor (Safety)

Air Flow Rate (L/min) For piston speed calculation (optional)

Cycles per Minute For air consumption calculation

Cylinder Type

About This Calculator

This pneumatic cylinder sizing calculator supports both quick bore estimates and advanced configuration with metric/imperial units, single/double acting modes, and reverse force-to-bore calculation. It uses Pascal's principle to determine the theoretical and actual force output of a pneumatic cylinder. It accounts for rod diameter reduction on the retract stroke, applies a user-selectable load factor for real-world safety margin, and estimates free air delivery (FAD) consumption for compressor sizing. Browse all pneumatic calculators for related tools including air compressor sizing and compressed air pipe sizing.

Results

Push Force (Extend)

1,178.1 N

Pull Force (Retract)

989.6 N

Effective Force (with Load Factor)

765.8 N

Recommended Standard Bore

50 mm

Air per Cycle (FAD)

2.501 L

Air Consumption (FAD)

25.0 L/min

Piston Speed (Extend)

1,697.7 mm/s

Continue Your Calculation

After cylinder force and air consumption, size the compressor for total CFM demand and the piping for pressure drop.

Size compressor →

Standard Pneumatic Cylinder Bore Sizes #

Select the next standard bore size larger than your calculated minimum bore. ISO 6432 defines metric standard bores for micro cylinders, while ISO 15552 (formerly ISO 6431/VDMA 24562) covers larger industrial cylinders. NFPA defines imperial standard bores for the North American market.

Standard	Bore Sizes	Typical Application
ISO 6432 (metric micro)	8, 10, 12, 16, 20, 25 mm	Small automation, clamping, light assembly
ISO 15552 (metric industrial)	32, 40, 50, 63, 80, 100, 125, 160, 200, 250, 320 mm	General industrial automation, packaging, material handling
NFPA (imperial)	9/16, 5/8, 3/4, 1 1/16, 1 1/4, 1 1/2, 2, 2 1/2, 3, 4, 5, 6, 8 inch	North American machinery, mobile equipment
Compact / Short Stroke	12, 16, 20, 25, 32, 40, 50, 63, 80, 100 mm	Space-constrained installations, ejection, pressing

Source: ISO 6432:2015, ISO 15552:2018, NFPA T3.6.1 R1-2014. Always verify exact dimensions and mounting patterns with the cylinder manufacturer's datasheet.

Formulas and Calculation Method #

Force Calculation

Pneumatic cylinder force is derived from Pascal's principle: pressure acts uniformly on the piston area. The theoretical force depends on whether the cylinder is extending or retracting:

Push (extend): F_push = P × π × D² / 4
Pull (retract): F_pull = P × π × (D² - d²) / 4
Effective force: F_eff = F_theoretical × load_factor

Where: D = bore diameter, d = rod diameter, P = gauge supply pressure (absolute for FAD calculations). The rod diameter reduces the effective piston area on the retract side, so pull force is always less than push force for the same bore and pressure.

Bore Sizing (Reverse Calculation)

When the required force is known, solve for the minimum bore diameter:

D_min = sqrt(4 × F_required / (π × P × load_factor))

After calculating D_min, select the next larger standard bore size from the reference table above. This ensures the cylinder can produce the required force even at the minimum available system pressure, accounting for pressure drops in filters, regulators, valves, and tubing.

Air Consumption

Air consumption is calculated as the total swept volume per cycle, converted to free air delivery (FAD) at atmospheric pressure:

Extend volume: V_ext = π/4 × D² × S
Retract volume: V_ret = π/4 × (D² - d²) × S (double-acting only)
Per cycle (FAD): V_cycle = (V_ext + V_ret) × (P_gauge + P_atm) / P_atm
Continuous consumption: Q = V_cycle × cycles_per_minute

Single-acting cylinders consume air only on the power stroke (extend), with the return stroke driven by spring or external load. The pressure ratio converts compressed volume to equivalent free air, which is what the compressor must deliver.

Piston Speed

Given a known air flow rate, the average piston speed is:

v = Q / A = 4Q / (π × D²) (convert Q to consistent volume/time units)

Typical pneumatic cylinder speeds range from 50-500 mm/s. Speeds above 500 mm/s require cushioning at stroke end to prevent impact damage. The actual speed is limited by valve flow capacity (Cv), port size, and exhaust muffler restriction, not just supply flow.

Force Reference Chart (6 bar / 87 PSI) #

Quick reference for theoretical push force at common supply pressure of 6 bar (87 PSI), with 65% load factor applied for effective working force. Rod diameter assumed as 50% of bore for retract force.

Bore (mm)	Push (N)	Pull (N)	Effective Push (N)	Air/Cycle (L FAD)	Typical Application
16	121	91	79	0.18	Small clamping, sorting gates
25	295	221	192	0.44	Light assembly, label applicators
32	483	362	314	0.72	General automation, pushers
40	754	566	490	1.13	Packaging, conveyors, clamping
50	1,178	884	766	1.77	Material handling, lifting assists
63	1,870	1,403	1,216	2.81	Heavy clamping, pressing, lifting
80	3,016	2,262	1,960	4.52	Heavy pressing, die casting, stamping
100	4,712	3,534	3,063	7.07	Very heavy loads, industrial presses

Assumptions: 6 bar gauge supply, rod diameter = 50% of bore, 100 mm stroke, 65% load factor. Air/cycle values are FAD (free air delivery). Actual values vary by cylinder manufacturer and system configuration.

Frequently Asked Questions #

What is the formula for pneumatic cylinder force?

The theoretical push force (extending) is F = P × π × D² / 4, and pull force (retracting) is F = P × π × (D² - d²) / 4, where D = bore diameter, d = rod diameter, P = supply pressure. Apply an efficiency factor of 0.7-0.9 for real-world force due to seal friction and pressure losses.

How do I choose the right bore size for my cylinder?

Calculate the minimum bore using D = sqrt(4F / (π × P × η)), then select the next larger standard bore size. Common standard bores per ISO 6432 are: 8, 10, 12, 16, 20, 25, 32, 40, 50, 63, 80, 100, 125, 160, 200, 250 mm. Always verify the cylinder can produce the required force at the minimum available system pressure after line losses.

What is the difference between single-acting and double-acting cylinders?

Single-acting cylinders use air pressure to extend and a spring or external load to retract. They consume air only on the extend stroke and are simpler but limited in stroke length. Double-acting cylinders use air pressure for both extend and retract, providing controlled force in both directions and are the most common choice for industrial automation.

How much air does a pneumatic cylinder consume?

Air consumption per cycle equals the total swept volume: extend volume = π/4 × D² × S, retract volume = π/4 × (D²-d²) × S (double-acting only). Convert to free air delivery (FAD) by multiplying by the absolute pressure ratio (P_gauge + 1.013) / 1.013. Multiply by cycles per minute to get CFM or L/min demand on the compressor.

What load factor should I use for cylinder sizing?

Use a load factor (ratio of actual load to theoretical force) of 0.5-0.7 for dynamic applications with acceleration, 0.7-0.85 for slow/steady loads, and 0.85-0.95 for static holding only. A lower load factor provides a safety margin and extends cylinder life by reducing seal wear and side loading.