Two-Gear Speed Ratio Calculator
Estimate driven speed and ideal torque multiplication from two gear tooth counts.
Your result
EVERYDAYEnter your values and select calculate.
On this page How it works & practical examples
How to use the Two-Gear Speed Ratio Calculator
Treat the entered gears as a single directly meshing pair. The ratio is driven teeth divided by driver teeth, and the output speed is a magnitude.
The calculation
Worked example
20 driver teeth and 60 driven teeth at 1,200 rpm give 400 driven rpm and ideal 30 N·m torque from a 10 N·m input.
Assumptions and limits
Ideal lossless model; strength, backlash and efficiency are excluded. A directly meshing external pair reverses direction, while additional gears change the direction and total ratio.
Common questions
Which inputs should I use?
Treat the entered gears as a single directly meshing pair. The ratio is driven teeth divided by driver teeth, and the output speed is a magnitude.
What does the result exclude?
Ideal lossless model; strength, backlash and efficiency are excluded. A directly meshing external pair reverses direction, while additional gears change the direction and total ratio.