Our preference data is composed of a set of name->value pairs. The setting names are often "namespaced" with dot ('.') separated words. Many JOSM plugins will store preferences grouped in a namespace.

You can get a similar raw view by viewing this file, but this 'Advanced' preferences panel is intended to provide a easier alternative.


Most of the settings can be reached via menus

Other preferences

JOSM preference/data/cache directories

JOSM stores 3 kinds of files in different directories:

Configuration data and settings, such as authentication for the OSM server, list of last opened files, selection of expandable dialogs on the right, etc.
User data
User specific data files, for example autosave data, plugins and ignored validator errors
Files downloaded from the internet and stored for a limited time to avoid repeated downloads and allow faster access. For example imagery tiles and startup news.

The default location of the directories depends on your operating system.


Preferences and user data is stored in


To locate this folder, try opening Explorer window and paste following text in location, then hit enter: %APPDATA%\JOSM, On Windows Vista and later, it should be something like C:\Users\<YourName>\AppData\Roaming\JOSM. Note, that the directory C:\Users\<YourName>\AppData can be hidden by default.

The cache is located in


for Windows Vista and later.

This is typically C:\Users\<YourName>\AppData\Local\JOSM\cache.

On Windows XP and earlier, the cache is in %APPDATA%\JOSM\cache.

Mac OS X

On Mac OS X, the default locations are as follows:

User data


Since r11162, JOSM uses the XDG Base Directory Specification for fresh installations, i.e.

User data

JOSM respects the $XDG_CONFIG_HOME, $XDG_DATA_HOME and $XDG_CACHE_HOME environment variables to chance these locations.

Prior to r11162, the locations were

User data

JOSM will continue to use the old locations, if the directory $HOME/.josm exists. If you have a fresh installation, but prefer the old scheme, you can create the $HOME/.josm directory by hand.

Note on hidden files: File names beginning with a dot are hidden on Linux. To show the contents of the hidden folder, use the file manager and enter "~/.josm" in the address line (if no address line is visible just try to enter a letter and hopefully a popup to enter the address will open). Alternatively it is possible to "show hidden" files and folders in the file manager, using the keyboard shortcut Ctrl+H.

Customization (all operating systems)

Setting all 3 locations

The locations can be set using system properties specified from the commandline:

User data

For example to store the cache in D:\cache\JOSM, you would need to run a command like this:

java -Djosm.cache=D:\cache\JOSM -jar josm.jar

Setting a common directory

Alternatively, all 3 locations can be moved to a common location using the system property -Djosm.home=.... For example with

java -Djosm.home=D:\myJOSM -jar josm.jar

the locations change to

User data

Changing the directory base name

Instead of specifying the full path for the JOSM directories, you can use the system property to modify just the name of the last directory component, which is JOSM by default. This is especially useful in order to keep multiple profiles on one computer, which should not interfere. For example to have one profile for productive work with the stable tested version and one for the experimental development version, you would start the development version like this:

java -jar josm-latest.jar

On Linux, the directories would then change to

User data

(For locations in the style prior to r11162, the lower-case version with prepended dot will be used, e.g. $HOME/.josm-dev.)

preferences.xml Schema

Some descriptions can be found in Help/Preferences/ImportExport (stub)

Auto save subfolder

Utilized by autosave function.

See also

Last modified 4 months ago Last modified on 2016-11-27T09:33:29+01:00