Gear Speed Calculator with transparent formulas, clear units, and instant results. Top-gear speed: V = RPM × C × 60 ÷ (G₁ × G₂ × 1000).
Stable formula
This calculator uses a stable mathematical formula. Always verify the values you enter.
Accuracy level
High when inputs and units are correct.
Last reviewed
July 9, 2026
Formula or source
Stable mathematical formula explained on the page.
Guide reading time
4 min
Confidence
High for the stated calculation.
Result type
Formula result, not an official certification.
Do not use for: Cases with missing data, unclear units, or a required professional certification.
How Gear Speed Calculator works
The Gear Speed Calculator uses these inputs: Gear ratios separated by commas, Final drive ratio, Tire diameter (mm), Maximum RPM. Its primary output is Top-gear speed. Performance tools use theoretical relationships between power, RPM, gearing, and engine geometry.
The engine implements V = RPM × C × 60 ÷ (G₁ × G₂ × 1000). Validation runs first to reject zero divisors and non-finite values.
Numeric example using the starting values: Gear Speed Calculator: Gear ratios separated by commas: 3.6,2.2,1.5,1.0,0.8 · Final drive ratio: 4.1 · Tire diameter (mm): 630 · Maximum RPM: 6500. The resulting output is Top-gear speed: 235.33 km/h.
Gear Speed Calculator: Limitation for Top-gear speed: the estimate covers only the displayed fields and does not model unentered road, wear, fitment, legal, or tariff conditions. Drivetrain loss, traction, air conditions, calibration, and mechanical condition are excluded unless entered.
💡 Useful Tips
Do not mix units between Gear ratios separated by commas and Final drive ratio; make sure both describe the same scenario. Use the result for engineering comparison, not as a performance guarantee or tuning instruction.
Do not treat Gear Speed Calculator — Top-gear speed as mechanical, safety, legal, or financial approval.
It is the direct output of the formula and entered values, and applies only to the defined scenario.
Which inputs change the result?
The active inputs are Gear ratios separated by commas, Final drive ratio, Tire diameter (mm), Maximum RPM. Changing any one runs the same formula again. A theoretical result does not replace dyno measurement or professional inspection.
What to check next
The result is a starting point. For a clearer picture, continue to a related calculator or read a short guide that explains the assumptions.