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Cartahaven

Free tool

Add location to a PDF map

Turn a scan, photo or plain PDF of a map into a GeoPDF that shows your GPS position. It’s free, with no account, and works best on a computer.

A USGS topo map in the Cartahaven app with the blue GPS dot, a track being recorded, and Layers, Tools, Mark, Record and Locate buttons along the bottom

How it works

  1. Choose your map. Your map appears on one side and a world map on the other.
  2. Click a spot you can recognize on your map, such as a road junction, a summit or a trailhead.
  3. Click the same spot on the world map. You can jump there by searching for a town, a park or a “lat, lon”.
  4. Repeat for at least three points, spread as far apart as you can.
  5. Save, then download your GeoPDF.

With four or more points, the tool shows an error estimate for each one, so you can drag or remove a point that looks off. For more on picking good points, see how to georeference a scanned paper map.

How accurate will it be?

It depends on your points and on the map itself. A hand-drawn or out-of-scale map won’t line up everywhere, however well you place the points. Treat the result as a guide, and check it against something you can recognize before you rely on it.

Your file stays on your device

Your map is read and written in your browser, so it isn’t uploaded to Cartahaven or anywhere else. The world map loads from OpenStreetMap, and a place you search for goes through our server to look it up. We count how often the tool is used and how it ends, never the file name or location.

Questions

Which files can I use?
PDF, JPEG, PNG and TIFF. Pictures are converted to a PDF first. For a multi-page PDF, you can place each page separately.
Will it open in other apps?
It writes the standard geospatial PDF format that GIS tools export. Our own map app reads it, and other GeoPDF readers should too, though we can’t test them all.
Can I do this on my phone?
Yes, though placing points is easier on a bigger screen. The Cartahaven map app can also place a map directly on your phone with “Use a photo of a paper map”.
Can I use it on any map?
Only on maps you have the right to copy and change. Adding location data doesn’t change who owns the map.