Roll Race Calculator is a performance tool built for racers, tuners, and car enthusiasts who want quick estimates from common Dragy-style roll-racing data.

Turn 60–130 mph, 100–150 mph, and 100–200 km/h times into useful performance estimates including horsepower, trap speed, race gaps, weight savings, DA correction, slope correction, and more.

Features include:

Horsepower Calculator
Estimate horsepower from roll-race times and vehicle weight. Supports common performance ranges like 60–130 mph and 100–200 km/h.

Trap Speed Estimator
Estimate trap speed from performance times using a chart-based lookup system.

Roll Race Gap Visualizer
Compare two cars using 60–130, 100–150, or combined roll-race data. Estimate the winner, time difference, distance gap, car-length gap, and losing car speed when the winner finishes.

Weight Savings Calculator
See how adding or removing weight can affect estimated performance.

DA Correction
Estimate how density altitude may affect performance and compare corrected results.

Slope Correction
Estimate how uphill or downhill grade may affect a run.

Car Comparison Tools
Compare two vehicles using common roll-race performance inputs.

Excuse Generator
Generate classic racing excuses for slow times, bad hits, traction issues, boost problems, weather, and more.

Roll Race Calculator is designed for quick, easy performance estimates without complicated setup. It is useful for street/strip racers, tuners, dyno shops, Dragy users, and anyone who likes comparing roll-race performance.

Important:
All results are estimates. Actual vehicle performance may vary based on weather, slope, road conditions, traction, gearing, shift points, driver input, vehicle setup, data accuracy, and other factors. This app is intended for informational and entertainment purposes only.

Always follow local laws and use safe, legal racing environments.