Data · Upload a file
Add accurate elevation to a GPX, KML, GeoJSON or CSV file
Add elevation to a GPX, KML, GeoJSON or CSV file from the LINZ 1 m LiDAR model: every point gets its ground height, replacing the noisy altitude from a GPS watch or phone, or filling a height column that was empty.
The file is read and written in your browser. Nothing is uploaded.

Free to run · pay to download
See the full result on the map free, with no account. Download the enriched file in its original format with a pass: NZ$49 for 7 days or NZ$299 for 12 months, one-off, GST included, not a subscription. Every download on the site is included while the pass lasts.
Who uses this
- Runners, riders and trampers. Fix the climb on a GPS track.
- Field and asset teams. Add heights to a CSV of poles, troughs or sample points.
When to use it
- Fixing the elevation on a GPS track from a watch or phone.
- Adding a height column to a CSV of sample points, poles, troughs or trees.
- Giving a drawn route real elevation before importing it into a planning tool.
Which tool for your job
Elevate a File is one step in a bigger question. These are the jobs it helps with, and the tools that go with it.
If you’re working on walks, runs and rides
How much climbing, and how far?
- 1.Elevation Profile — Distance, total climb and descent, and the steep sections.
- 2.Elevate a File (this tool) — Replaces the noisy altitude in a GPX from a watch or phone with LiDAR ground height.
- 3.Measure — A quick flat distance between points.
If you’re working on plans, cad, gis and 3d printing
I need the terrain as a file.
- 1.Download Data — Contours, a GeoTIFF elevation model or a 3D mesh for printing.
- 2.Contour Lines — Contours previewed on the map before you export them.
- 3.Elevate a File (this tool) — Adds ground elevation to your own GPX, KML, GeoJSON or CSV points.
- 4.Add Elevation — A single spot height, for a floor level or a tank.
- 5.Terrain Stats — The highest, lowest and mean ground height of an area, and how the land is spread between them.
How to use it
- Open Elevate a File and choose the file. It is read in your browser.
- For CSV, confirm which columns hold longitude and latitude.
- Run. The same file comes back with elevation added to every point. Downloading it needs a pass.
Step by step: Mt Iron, Wānaka
We fix the altitude in a GPX track of the Mt Iron walk recorded on a watch.


What it showed
- Open the new file in Strava, Garmin Connect or QGIS and the climb will match the ground rather than the watch's barometer.
Screenshots from NZ Elevation Tools. Aerial imagery from LINZ Basemaps. Sourced from the LINZ Data Service and licensed by Environment Southland, Otago Regional Council and Queenstown-Lakes District Council for re-use under the Creative Commons Attribution 4.0 International licence.
How it works
The file's coordinates are read, the LiDAR bare-earth model is loaded for their extent, and each point is sampled with interpolation between cells. The file is written back in its original format with the elevation field filled or added.
Reading the results
Elevations are ground level at each coordinate. For a track walked on the ground that is what you want; for a drone flight it is the terrain beneath, not the flight height.
Limits and warnings
- The points must fit inside a 6 km square. Split larger files.
- Where 1 m LiDAR has not been flown the tool falls back to the national 8 m elevation model, and the result says what share came from the fallback. The 8 m model was interpolated from 20 m map contours and is not fit for site-scale decisions.
- Nothing is uploaded to a server. The file never leaves your browser.
Data and attribution
Results come from the LINZ national 1 m LiDAR bare-earth elevation model, read in your browser, with the national 8 m model filling any gaps. Tools that use the surface model (Sunlight, Viewshed, Object Heights) read the matching LiDAR surface tiles.
Elevation and cadastral data is sourced from the LINZ Data Service and licensed for re-use under the Creative Commons Attribution 4.0 International licence. Copyright in each LiDAR survey belongs to the body that commissioned it — a regional or district council, Waka Kotahi, NIWA and around thirty others — rather than to LINZ, which hosts and processes the national dataset. Every file exported from this site names the licensors whose surveys cover the area, and anything you publish from those files carries the same attribution requirement. See https://www.linz.govt.nz/products-services/data/licensing-and-using-data/attributing-elevation-or-aerial-imagery-data
Questions
Does it work for drone flight logs?
It gives the ground height beneath each point, not the flight height. That is useful for height above ground, but it will not correct the flight altitude itself.
Ready to try it?
Open Elevate a File on the map →Free to use, no account. Runs in your browser on LINZ open data. Downloading the results needs a pass: see prices.