Preferences Overview

The preference data in JOSM is composed of a set of name->value pairs. The setting names are mostly namespaced with dot . separated words. Many JOSM plugins store their preferences grouped in a namespace.

You can get a similar raw view by viewing these files, but the preferences' panel source:trunk/resources/images/preferences/advanced.svg advanced preferences is intended to provide an easier alternative.

Most of the settings can be reached via menus in the source:trunk/resources/images/preference.svg preferences dialog, See the individual panel pages: Audio, BackupPreference, ColorPreference, Connection, Display, DrawingPreference, GPXPreference, Imagery, ImportExport, LanguagePreference, Map, MapPaintPreference, Plugins, ProxyPreference, RemoteControl, RovasConnector, Shortcuts, TaggingPresetPreference, Toolbar, Validator

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 and is listed in the Installation details tab of the source:trunk/resources/images/logo_48x48x32.pngAbout dialog in the Help menu


Preferences and user data is stored in


To locate this folder, try opening Explorer window and paste the 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.


On MacOS, 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 change these locations.

Prior to r11162, the locations were

User data

If JOSM is installed via flatpak, the locations are

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 command line:

User data

For example to store the cache located 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 the prepended dot will be used, e.g. $HOME/.josm-dev.)

preferences.xml Schema

See preferences-1.0.xml.

Some descriptions can be found in Custom configuration XML files for JOSM

Auto save subfolder

Utilized by autosave function.

See also

Back to Preferences dialog
Back to Main Help

Last modified 12 months ago Last modified on 2022-11-21T22:07:09+01:00