Route Time & Fueling Calculator

The elevation profile is resampled, smoothed to remove GPS noise, and merged into segments of near-constant grade — a new segment starts whenever the grade shifts by more than about 1.5% (so a climb that eases from 6% to 3% becomes two segments). For each segment, a physics model balances your power against gravity, aerodynamic drag, and rolling resistance to predict speed, using a pacing model based on your FTP: slightly harder on climbs, soft-pedaling on gentle descents, and coasting on steep ones.

Sports nutrition research recommends 30–60 g of carbohydrate per hour for rides lasting 1–2.5 hours, and 60–90 g/h for longer rides. Elite racers train their gut to absorb 90–120 g/h using glucose-fructose mixes. Under about 45–60 minutes, no in-ride fueling is needed. This calculator scales the recommendation to your predicted ride duration and intensity.

Intensity Factor is your normalized power divided by your FTP — an IF of 0.75 means you rode at 75% of your threshold. Training Stress Score combines intensity and duration into one workload number: one hour ridden exactly at FTP equals 100 TSS. Rides under 150 TSS typically need a day or less of recovery; over 300 TSS may need several. Read more in our guide on what TSS is and how to use it.

GPX files with elevation data (exported from Strava, Komoot, RideWithGPS, Garmin Connect, and most planning apps) and FIT files (courses or recorded activities from Garmin, Wahoo, and similar head units). The file is processed in your session and is not stored.

The model assumes steady pacing, no stops, no wind, and no drafting. Real rides include traffic lights, café stops, wind, group riding, and road surfaces that change rolling resistance. Treat the prediction as a well-informed baseline — most riders land within about 5–10% of it on solo, non-stop rides.