Automotive engineering calculators

Free tools for gearing, tyres and vehicle performance. Each one shows its formulas and sources, is covered by automated tests and states what it does not account for.

Tools

Drivetrain · Tyres

Gear ratio speed calculator

Speed in every gear, rpm at cruising speed, rpm drop on upshift and speedometer change with a different tyre size.

More tools are in progress. We publish a tool only once its formulas are sourced and tested.