Validator window

source:trunk/images/dialogs/validator.png Keyboard shortcut: Alt+Shift+V — one of the JOSM windows

The JOSM Validator is a feature of JOSM which checks and fixes invalid data.


  • Select the data you want to validate (or deselect to validate everything)
  • Click on the Validate button source:/trunk/images/dialogs/validator.png at the bottom of the validator panel or press Shift+V to run the validation process:
  • While some of the errors must be manually fixed, most of them can be automatically fixed. Just select the error or errors and click the Fix button source:/trunk/images/dialogs/fix.png to automatically fix them. You can select multiple errors, and all of them will be fixed.
  • Use right click menu to "Zoom to problem"
  • Multiple objects with the same symptom are grouped together

The validator is an automatic test tool. It can show you possible errors in the data, but it may also tell you errors, which aren't real.

Don't fix errors when you aren't sure something is really wrong

Validator will check the data and display all errors, categorized as errors source:/trunk/images/data/error.png, warnings source:/trunk/images/data/warning.png, and other source:/trunk/images/data/other.png, depending on the severity of the error. By default only warnings of level error and warning will be displayed. Warnings of level other produce a lot more validation errors for valid data and thus need more care from the user.

This window allows to start a verification process of the data.

You have five buttons in this:

  • source:/trunk/images/dialogs/select.png Select – Select the objects of the selected error.
  • source:/trunk/images/dialogs/search.png Lookup – Looks up the selected primitives in the error list
  • source:/trunk/images/dialogs/validator.png Validation – Start validation process for current selection or all objects (when nothing selected).
  • source:/trunk/images/dialogs/fix.png Fix – Fix an error (only when automatically fixable).
  • source:/trunk/images/dialogs/fix.png Ignore – Ignore an error or a group of errors in future tests.

When a validation process has been finished all results will appear in the list. Also a new validation layer is added, which shows you where problem cases lie in the map.

Validation on upload

When not disabled the validation process is also started on each upload to the server. For uploads only the modified elements are tested. If you abort the upload, The validator panel opens, if not already open, and the validation results are copied in the validation window, so they can be checked and fixed.

Validation layer

If not disabled through preferences a validator run will open a validator layer.

Validation result can depend on the downloaded area

Some validator tests include a check whether the tested object is in or out of the downloaded area to avoid false positives. The not downloaded area is displayed with a yellow hatching. Downloaded ways can end in the not downloaded area. If e.g. a waterway ends in the downloaded area then the validator warns that it should be connected to another waterway. If the waterway ends out of the downloaded area then the validator will not warn because it doesn't know if there is really an error because the possible connected waterway was not downloaded. The validator will also not warn if there was never an area download in this data layer (there is no yellow hatching in this layer). Such a layer exists when you e.g. create a new empty layer or when you download single objects via Overpass. In both cases the data is assumed as incomplete and handled like out of the downloaded area to avoid false positives and a lot unnecessary warnings.

Some validator rules are limited to defined areas (e.g. countries), see Territoryselectors.

Advanced Preferences

There are some advanced settings which can be changed in the advanced preference:

  • osm-primitives.showid: set to true/false to display/hide the osm id of the object in the list
  • osm-primitives.showcoor: set to true/false to display/hide the coordinates of the object in the list

See also

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Last modified 4 months ago Last modified on 2018-10-28T13:59:20+01:00

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