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Analyze your GPX or FIT file: speed, distance and best runs

Drop a GPX or FIT file from your watch or tracking app. You get top speed, best 10 seconds, best 500 m, the nautical mile, a speed chart and your track on a map in a few seconds. The file stays on your device.

What does the GPX analyzer measure?

It measures the fastest stretches of your session from the GPS track: top speed over 2 seconds, best 10 seconds, best 500 m, best nautical mile and best hour, plus distance, total and moving time.

Peak and 10 sYour fastest burst and your fastest full run, the numbers most riders compare.
500 m and nautical mileDistance-based averages, as used in speed sailing rankings.
Chart and trackYour track on a map, coloured by speed, with the best 10 seconds highlighted, plus speed over time.

What else can Waterspeed show from a session?

The Waterspeed app goes past speed: it breaks a session into tacks and gybes, foiling time, VMG and polar charts, and keeps your records over time.

Want VMG, tacks and gybes, foiling time and polar charts?To keep this session, import the file in Waterspeed: GPX in the iPhone or Android app (Diary, then the three-dot menu), FIT in the web app. Tacks, gybes and foiling come with Pro; VMG and polar charts with Ultra.
  • ProTacks and gybes analysisSee how clean and fast your turns really are.
  • ProFoiling efficiencyTrack foiling speed, time and distance to improve consistency.
  • UltraVMG optimisationAnalyse VMG point by point across charts and maps.
  • UltraPolar chartsCompare speed, wind strength and angles, and see where target speeds can improve.
Open the web appSee plans

Questions

Is my file uploaded?

No. The file is read by your browser and never leaves your device, and nothing is stored after you close the page. To draw the map, your browser loads map tiles for that area from OpenStreetMap.

Which files work?

GPX and FIT files of a recorded activity, with timestamps: the formats Garmin, Coros, Suunto and most watches, sailing instruments and tracking apps export. A planned route has no times, so it cannot be analyzed.

How is top speed measured?

Top speed is the best average over 2 seconds, which removes most single-point GPS spikes. Best 10 s, 500 m and nautical mile use the same sliding window over the whole track, as speed sailing rankings do.

Why does my watch show a different top speed?

Watches often show an instant value from a single GPS fix, which is noisier. Short gaps and impossible jumps (over about 87 knots) are also removed here, so the numbers can be a little lower.

How do I see VMG, tacks and gybes or foiling time?

Open the Waterspeed web app or the mobile app. Tacks and gybes analysis and foiling efficiency are in the Pro plan; VMG optimisation and polar charts are in Ultra.