Gear Ratio Calculator
Ratio and output RPM from tooth counts.
Amortization schedule
| # | Payment | Principal | Interest | Balance |
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Showing first 12 of months.
Growth over time
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Introduction
Gear Ratio Calculator — Ratio and output RPM from tooth counts. Enter Driver gear teeth, Driven gear teeth, Input RPM to get an instant, accurate result.
Formula
Gear ratio = driven teeth / driver teeth. Output RPM = input RPM / gear ratio.
Step-by-step
- Enter the Driver gear teeth.
- Enter the Driven gear teeth.
- Enter the Input RPM.
- Click Calculate to see your result instantly.
Real-world example
Example: With Driver gear teeth = 20, Driven gear teeth = 40, Input RPM = 1000, the Gear Ratio Calculator gives Ratio: 2, Output Rpm: 500.
Frequently Asked Questions
What does a ratio greater than 1 mean?
The output shaft turns slower than the input (a reduction), trading speed for torque.
Does this account for gear efficiency losses?
No, it's an ideal mechanical ratio without friction or efficiency losses.
What inputs does the Gear Ratio Calculator need?
You'll need to provide: Driver gear teeth, Driven gear teeth, Input RPM. All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.
How accurate is the Gear Ratio Calculator?
The Gear Ratio Calculator applies the formula exactly as calculated — Gear ratio = driven teeth / driver teeth. Output RPM = input RPM / gear ratio. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.
Is the Gear Ratio Calculator free to use?
Yes, the Gear Ratio Calculator is completely free, requires no signup, and runs instantly in your browser.
About the Gear Ratio Calculator
The Gear Ratio Calculator uses a real, verifiable formula — Gear ratio = driven teeth / driver teeth. Output RPM = input RPM / gear ratio. — so results are accurate every time, not an approximation.