Chain Drive Calculator

Formula

• Design power = Input power × Service factor × Lubrication factor
• Chain length in pitches from standard roller chain geometry
• Safety factor = Chain breaking load ÷ Chain tension

About this calculator

Part of our Mechanical Calculators collection. Beams, bolts, springs, gears, bearings, and core ME calculations.

How it works

Design power includes service and lubrication factors. Chain length in pitches and corrected center distance follow standard roller chain geometry. Compare the actual safety factor to your application requirement before ordering chain.

Enter your values in the inputs above and click CALCULATE. Results appear on the right without a page reload. No login and no server upload.

Worked example

5 kW, #50 chain, Ks = 1.4, driver 19 teeth at 1450 rpm.

1. Design power = 5 × 1.4 = 7 kW
2. Chain speed and tension computed from teeth, pitch, and rpm
3. Safety factor compared to chain breaking load

Result: Review safety factor (target 7+ for typical drives) and recommended chain index.

When to use

• Roller chain drive preliminary sizing
• Calculating chain length in pitches for ordering
• Checking if current chain size is adequate

Limitations

• Single strand, ANSI roller chain
• Power ratings are approximate and speed-dependent
• Minimum 17 teeth on small sprocket assumed

FAQ

Why must driver teeth be at least 17?

Small sprockets increase chain wear and reduce life. ANSI practice uses 17 or more teeth on the driving sprocket.

What safety factor is acceptable?

Many drives target 7 to 10 based on breaking load versus working tension. Lower values need a larger chain.

Why is chain length always even pitches?

Roller chain uses a master link on an even number of pitches so end pairs match.