Quality assurance – OpenStreetMap Wiki

See also: Accuracy, Completeness

Quality Assurance tools help lead to better quality of OSM data. Often, the tools achieve this by providing a list of bugs in the data, which mappers can then go and fix using editing tools. The bugs are either automatically detected based on rules and data analysis, or the tools provide a means of manually reporting them, or some combination of the two. There are many different ideas for how to do this, and what kind of bugs to focus on, hence many different tools.

OpenStreetMap is often more up-to-date and of a higher quality than other commercial maps when dealing with New and Changed Ways.

It is important to understand that warnings are just warnings, they should be examined and fixed where possible but never at the cost of introducing wrong data. Some validators warnings are generated for valid data. Often in such cases validator code should be fixed, not OSM data. Sometimes false positives are unavoidable.

These are tools that try to highlight and point out parts of the data that are likely wrong. There are also reports from manual quality checks by humans. In both cases, the reported issues may contain false positives and, when editing, care should be taken to ensure their accuracy. However, they can provide a very valuable visualisation of which areas need attention and can help spot and correct errors.

• Notes

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  Notes is a feature of the OpenStreetMap website. Error reports can be added by using the ‘Add a note’ button in the lower right corner.

Error Detecting Tools check the OSM data for potential data errors, inaccuracy or sparsely mapped places. Users should check if these structures are really wrong (false positives usually occur and there are not really mapping rules which are set in stone) and correct the data for a continuously rising data quality.

Comparison of some of the following tools

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Tool

Coverage

Error types

Display mode

Fix suggestion

Downloadable

API

Correction guide

Development

Quality

JOSM/Validator

Local (scan data downloaded into editor)

Many

List + map

yes

yes

N/A

For some problems

Active

The best OSM validator, very few false positives, false positives are quickly fixed

Osmose

World

Many (200+)

Marker map

yes

yes

yes

yes

Active

Many irrelevant, unimportant or misleading complaints

OSM Inspector

World/Partial

Many

Rendered map

no

yes

N/A

no

Active

MapRoulette

World/Partial

Many (10+)

One feature at time

yes

yes

yes

no

Active

Reports are user provided, range from excellent to actively harmful

BRouter Suspects

World

Car Routing

List or Osmoscope

no

no

no

no

Active

Nominatim QA

World

Addressing, places

Marker map

yes

?

?

?

Active

Excellent, but limited to issues impacting Nominatim

Keep Right

World

Many (50+)

Marker map

no

yes

yes

German only

Inactive (last commit 2017)

https://cdn.organicmaps.app/subway/ — refreshed multiple times daily

https://github.com/alexey-zakharenkov/subways — active repository fork

https://maps.mail.ru/osm/tools/subways/latest/ — weekly refreshed validation results

https://maps.mail.ru/osm/tools/subways/ — history of recent validations

https://maps.mail.ru/osm/tools/subways/validate/ — validator trigger (please do not overuse)

https://maps.mail.ru/osm/tools/subways/latest/mapsme.json — file suitable for routing over validated rapid transit systems, including transfers.

• Atlas Checks

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  Atlas Checks are a suite of open-source data quality checking tools using the Atlas framework and Spark. There are a number of different checks looking at topology issues, tags, and more looking at all kinds of OSM data. The results can be used in MapRoulette or in JOSM or your favorite editor. Currently a number of different organizations use Atlas Checks as well.

• OpenStreetMap Wikidata Quality Checker

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  The OpenStreetMap Wikidata Quality Checker searches for invalid or inaccurate links between OpenStreetMap and Wikidata by evaluating Wikidata tags. The issues found are reported to Osmose.

• OSM-wikipedia-tag-validator-reports

  Lists cases where wikipedia=* wikidata=* are invalid or broken for variety of reasons. Includes some checks not supported by other QA tools, but is refreshed less often than many QA tools.

• OSM highway name interpolation (ohni)

  The OSM highway name interpolation (ohni) script finds unnamed highways in OSM data whose name can be derived from neighbouring ways and thus be armchair-mapped. (False-positives are possible, use common sense!)

• Pedestrian overlay

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  [4] – A map of pedestrian/walking data; useful when checking coverage or connectivity of pedestrian mapping.

  It aims to show pedestrian mapping coverage (how many of the pedestrian-taggable elements are tagged with pedestrian data); this may be useful to see how well an area is mapped for pedestrians.

  It also aims to give an idea of connectivity (how well elements are connected, i.e. whether pedestrian elements have nodes connected to each other via nodes, for example, sometimes pedestrian elements are mapped without showing how they connect, for example a path which connects to a sidewalk may not yet have a node connecting one another); this information may be helpful for those working on routing.

• OSRM debug option

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  [5] – The debug option of the OSRM demo page provides a map overlay of the highways’ speeds calculated by OSRM.

• OSM Lane Visualizer

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  [6] OSM Lane Visualizer is a tool to show several attributes of a highway, selected by a overpass query or by relation id.

• Parking lanes viewer from OpenStreetMap

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  [7] Parking lanes viewer from OpenStreetMap is a map to show street parking attributes of a highway. The source code is located under: .

Note: As of December 2022 the tool uses the deprecated parking:lane=* schema and is therefore not up to date.

• Bus lanes viewer from OpenStreetMap

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  [8] Bus lanes viewer from OpenStreetMap is a map to show attributes of a highway, such as lanes:bus=* or lanes:psv=*, the source code is located under: .

In addition to the above error and bug reporting tools, there are a number of tools that allow you to spot erroneous changes and edits. For example if you are very familiar with an area and have thoroughly mapped it, you might want to follow all changes and verify that no unintended damage or vandalism has happened in the area. The Planet History includes all changes that have been made, but might not be as easy to use.

In case that a change is bad (by ‘mistake’ or vandalism) you can rollback the change.

The following and other tools also listed on the List of OSM based Services page. For approaches to automatically detect suspicious changesets see Detect Vandalism. For monitoring tools on notes, see Notes#Monitoring notes in a selected area.

• Traffic Sign Tool

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  Traffic Sign Tool / Verkehrszeichen_Tool (de) – Assistant to get the right tags for German road signs.

• Road lists

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  Users in Germany requested different official lists: Straßenverzeichnis.

• CheckTheMonuments

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  Check The Monuments! More Quality for the Key Monument.

• Overpass turbo

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  Overpass API and the interface Overpass turbo lets you easily create custom queries which can be used to detect potential errors. The results get shown on a map with object detail links in popups and can be easily opened in JOSM. The example page lists some quality assurance uses.

• (Missing) Maxheight map

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  The Maxheight Map (aka OSM Truck QA Map) (website) is a Overpass API-based browser tool which helps you check and improve truck relevant features in OSM. Besides identifying missing maximum height tags under (railway) bridges and tunnels, you can also validate existing tagging for maximum height, width, length and weight amongst others.

• OSM Quality Assurance Editor (by osmsurround)

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  The OSM Quality Assurance Editor (website) helps to highlight (via Overpass API) missing data in several categories (tracks without tracktype tag, tracks without surface tag, streets without any sidewalk tag, ways without incline tag, ways without surface tag, ways without smoothness tag, buildings without address, residential without name) and allows to directly edit the objects via a built-in online editor.

• Public Transport Network Analysis (PTNA)

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  PTNA finds and aggregate information about public transportation lines mapped in OSM. Additionally a quality assurance is integrated. GTFS data is visualized and tags for route relations recommended.

• StreetComplete detects missing or incomplete data and allows to easily add it while surveying (Android application)

Tag statistics

To compare the use of a tag or to see typos, use these statistical tools. See also: Statistics.

• Taginfo

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  Taginfo is a system for finding and aggregating information about OSM tags and making it browsable and searchable.

• OSM Tag History

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  OSM Tag History displays the number of times a key or a key-value pair has been used as a function of time on a visual graph

• ohsome

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  The ohsome dashboard and API allow to perform in-depth analysis of the development of OSM data.

Other

External compares

See also: Research

See also