Find your fastest 1K, 5K, 10K, half marathon and more hidden inside any GPX, TCX or FIT file. See it highlighted on a map, or download it as its own file.
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Nice pace!
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A long run rarely has one single pace. There's usually a faster stretch buried somewhere in the middle, or the last kilometre you pushed harder than you realised. Strava calls this a Best Effort and shows it automatically once you upload a run, but that only works if the activity ends up on Strava in the first place. This tool does the same calculation directly on the file, before it goes anywhere.
For every standard distance that actually fits inside your route, it slides a window along your recorded points looking for the stretch where that exact distance took the least time, and does it for 1K, 1 mile, 5K, 10K, 15K, 20K, half marathon and marathon all in one pass. Whichever one you pick gets highlighted on the map so you can see exactly where it happened, and you can download it as its own small file if you just want that one stretch.
FAQ
For each standard distance that fits inside your route (1K, 1 mile, 5K, 10K, 15K, 20K, half marathon, marathon), it finds the single continuous stretch where you covered that distance in the least time. That's the same thing Strava calls a Best Effort, calculated directly from your file instead of an account.
It's worked out purely from your recorded GPS points, so the result is only as precise as those points are spaced. A window is built up to the first point where the cumulative distance reaches the target, which can land a few metres past it rather than exactly on it, close enough to compare efforts but not necessarily identical to a device's own internal calculation.
It works on the raw points and timestamps in your file regardless of sport, so yes, though the standard distances offered (1K through marathon) are chosen with running and walking in mind. For a ride you'd naturally get very short "fastest" times at the shorter distances, which is expected, just not usually the most interesting number for that activity.
Yes. Once you've picked a distance in the list, a download button gives you that exact stretch as a standalone GPX file.
No. Reading the file and finding the fastest segments both happen entirely in your browser. Nothing is sent anywhere, and no account is involved.
Only distances that actually fit inside the route are shown; a 3K run simply won't list a 5K or 10K effort.
No. It only looks at distance covered and time elapsed, so a fast downhill stretch or a slow climb both count exactly as recorded.
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