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Author: nrenner/achavi/graphs/contributors
License: MIT License (free of charge)
Platform: Web
Version: (2018-04-19)
Language: english
Source code: nrenner/achavi
Programming languages: JavaScript, HTML, and CSS

achavi (Augmented OSM Change Viewer) displays OpenStreetMap changes based on the Overpass API Augmented Delta (adiff) query and the returned Augmented Diff format.


Changeset Viewer

Achavi's changeset viewer, can be used to see the contents of a changeset displayed on a map. A very similar tool is OSM History Viewer.

This feature can easily be accessed via the two available services of WhoDidIt (the "[A]" link in the popup after you click a highlighted rectangle).


  • Does not work with changesets older than September 2012, see Overpass API attic data restriction.
  • Changesets from the last few minutes won't appear. The Overpass API needs to sync first.
  • The changeset feature is rather experimental and has some known issues.
  • For large (big map section) changesets visualization not done, e.g. example changeset occasional information message appears: says: "osmDiff: runtime error: Query run out of memory using about 2048 MB of RAM."

Browser extensions

Browser add-ons to jump from OSM changeset page to achavi:



Use a bookmarklet to conveniently access the tool! By clicking on the bookmarklet (or opening it via a keyword) while visiting a changeset page such as 18986223, you will get a new tab/window with the analysis page for that changeset.

javascript:(function(){ id=location.href.match(/www\.openstreetmap\.org\/changeset\/(\d+)/); if(id!=null){''+id[1]);} else{alert('This is not a valid OSM changeset page.')} })()

(Credits to Eugene and The knife)

Augmented Delta ("adiff") Viewer

Achavi can also display the results of your custom Augmented Diff query. Drag&drop a file onto the map or use the url parameter:
  • The results should be in a valid adiff xml format.
  • Do not forgot to add the full geometry to each object with the geom parameter of the out action.
  • If your custom url does not use secure connection (https) then you also need to change the url of the achavi to http.

See also