Keep the journey.

What is OnTrail Studio?

OnTrail Studio is a free browser-based tool for cleaning, simplifying and preparing GPS tracks for sharing and for navigation apps or devices with file-size and point-count limits. Add your files, choose the options, review the map and warnings, then download the result.

Clean and simplify

Remove GPS drift during stops while keeping entry and exit points and stop duration. Simplify routes by deviation tolerance or target point reduction. Coordinate precision can remain Original or be rounded to 6 or 5 decimal places. Compare the original and processed routes on the map. Reduction depends on the source: a percentage target is not guaranteed, and fewer points do not guarantee unchanged navigation accuracy. Rounding adds a small positional error; the map previews coordinates before rounding.

Fix recording mistakes

Split at recording gaps removes straight connections when both the time and distance thresholds are reached. Loose GPX downloads use numbered parts; ZIP batches retain filenames and store the parts as separate segments or geometries. Trim after sustained high speed finds a prolonged fast section anywhere in a track and removes everything from its start onward, including later stops or walking. It detects speed, not transport type: adjust the thresholds and review the result. Time-based cleanup requires usable timestamps.

Formats and batch processing

Load GPX, KML or KMZ files, or one ZIP archive at a time. ZIP batches preserve folder paths, filenames and native formats, including KML inside KMZ. KML/KMZ folders, names, styles and resources are retained; loose GPX output uses an optimized suffix or numbered parts. Other archive files remain unchanged. Progress is shown during processing; the archive map previews only the first successfully processed track. Check the completion report: files that cannot be processed are normally retained unchanged. KML processing supports route lines and tracks; polygon-only or point-only files are not supported, and external links are not fetched.

Join tracks

Select multiple loose files, arrange them manually or by start timestamp, and download a separate joined.gpx. Review the adjustable distance warnings (500 m by default). Joining draws straight connections; it does not calculate a walkable route. It switches off gap splitting, while other cleanup runs on each source before joining. Existing segments within selected files are also connected. Joined GPX retains route points and available elevations and times, but not KML styling, folder structure, attachments or standalone placemarks. Individual native exports remain available.

Photo waypoints

Load loose JPG/JPEG photos alongside tracks. Make waypoints from photos uses photo GPS first. Optionally enable Locate photos using track time for photos without GPS and adjust camera time in minutes. Both options are off by default. EXIF timezone offsets are respected; without one, camera time is treated as UTC (use +180 minutes for a camera on UTC−3). Names include the filename and available capture time. Missing or ambiguous matches, removed track sections and long recording gaps are skipped; the default interpolation limit is 300 seconds. Estimated positions depend on camera-clock accuracy and track sampling. GPS photo points are added to each individual output; time-matched points go to their matching track. Joined output includes each photo once. Photos themselves are not embedded; images inside ZIP archives are kept unchanged.

Archive size and practical limits

Fewer track points do not always mean a smaller archive. Download all tracks as ZIP packages individual outputs without additional compression. Processed ZIP/KMZ archives may also grow because of different compression, XML rewriting, retained resources or added waypoints. The reduction percentage describes point count, not file size. Input ZIP/KMZ is limited to 512 MiB, declared expanded contents to 1 GiB per archive, and each extracted entry to 128 MiB. Standard ZIP with stored or DEFLATE entries is supported; password-protected, multi-volume and ZIP64 archives are not. Available browser memory can impose lower practical limits, especially on phones. Split large collections into smaller batches. Joining and photo-waypoint creation are available for loose files, not ZIP batches.

Privacy and browser tips

Track and photo processing happens locally; their contents and filenames are not uploaded to our servers. Anonymous usage counters are sent, and optional OpenStreetMap tiles are requested for the area you view. Page opens are not unique users. Keep your originals and download results before closing or refreshing the page. Use a current browser. If file selection fails inside Facebook or Instagram, open the page in Safari or Chrome.