NZ Elevation ToolsOpen Elevate a File on the map →

Data · Upload a file

Elevate a File

Adds accurate ground elevation to the coordinates in a GPX, KML, GeoJSON, JSON or CSV file you already have, replacing missing or noisy GPS altitude.

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.

How to use it

  1. Open Elevate a File and choose the file. It is read in your browser.
  2. For CSV, confirm which columns hold longitude and latitude.
  3. Run. Download the same file with elevation added to every point.

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

Ready to try it?

Open Elevate a File on the map →

Free, no account. Runs in your browser on LINZ open data.