11 KiB
Reverse Geocoding
Reverse geocoding generates an address from a coordinate given as latitude and longitude.
How it works
The reverse geocoding API does not exactly compute the address for the coordinate it receives. It works by finding the closest suitable OSM object and returning its address information. This may occasionally lead to unexpected results.
First of all, Nominatim only includes OSM objects in its index that are suitable for searching. Small, unnamed paths for example are missing from the database and can therefore not be used for reverse geocoding either.
The other issue to be aware of is that the closest OSM object may not always have a similar enough address to the coordinate you were requesting. For example, in dense city areas it may belong to a completely different street.
Endpoint
The main format of the reverse API is
https://nominatim.openstreetmap.org/reverse?lat=<value>&lon=<value>&<params>
where lat and lon are latitude and longitude of a coordinate in WGS84
projection. The API returns exactly one result or an error when the coordinate
is in an area with no OSM data coverage.
!!! tip The reverse API allows a lookup of object by coordinate. If you want to look up an object by ID, use the Address Lookup API instead.
!!! danger "Deprecation warning"
The API can also be used with the URL
https://nominatim.openstreetmap.org/reverse.php. This is now deprecated
and will be removed in future versions.
Parameters
This section lists additional parameters to further influence the output.
Output format
| Parameter | Value | Default |
|---|---|---|
| format | one of: xml, json, jsonv2, geojson, geocodejson |
xml |
See Place Output Formats for details on each format.
| Parameter | Value | Default |
|---|---|---|
| json_callback | function name | unset |
When given, then JSON output will be wrapped in a callback function with the given name. See JSONP for more information.
Only has an effect for JSON output formats.
Output details
| Parameter | Value | Default |
|---|---|---|
| addressdetails | 0 or 1 | 1 |
When set to 1, include a breakdown of the address into elements. The exact content of the address breakdown depends on the output format.
!!! tip
If you are interested in a stable classification of address categories
(suburb, city, state, etc), have a look at the geocodejson format.
All other formats return classifications according to OSM tagging.
There is a much larger set of categories and they are not always consistent,
which makes them very hard to work with.
| Parameter | Value | Default |
|---|---|---|
| extratags | 0 or 1 | 0 |
When set to 1, the response include any additional information in the result that is available in the database, e.g. wikipedia link, opening hours.
| Parameter | Value | Default |
|---|---|---|
| namedetails | 0 or 1 | 0 |
When set to 1, include a full list of names for the result. These may include language variants, older names, references and brand.
Language of results
| Parameter | Value | Default |
|---|---|---|
| accept-language | browser language string | content of "Accept-Language" HTTP header |
Preferred language order for showing search results. This may either be a simple comma-separated list of language codes or have the same format as the "Accept-Language" HTTP header.
!!! tip First-time users of Nominatim tend to be confused that they get different results when using Nominatim in the browser versus in a command-line tool like wget or curl. The command-line tools usually don't send any Accept-Language header, prompting Nominatim to show results in the local language. Browsers on the contrary always send the currently chosen browser language.
Result restriction
| Parameter | Value | Default |
|---|---|---|
| zoom | 0-18 | 18 |
Level of detail required for the address. This is a number that corresponds roughly to the zoom level used in XYZ tile sources in frameworks like Leaflet.js, Openlayers etc. In terms of address details the zoom levels are as follows:
| zoom | address detail |
|---|---|
| 3 | country |
| 5 | state |
| 8 | county |
| 10 | city |
| 12 | town / borough |
| 13 | village / suburb |
| 14 | neighbourhood |
| 15 | any settlement |
| 16 | major streets |
| 17 | major and minor streets |
| 18 | building |
| Parameter | Value | Default |
|---|---|---|
| layer | comma-separated list of: address, poi, railway, natural, manmade |
unset (no restriction) |
The layer filter allows to select places by themes.
The address layer contains all places that make up an address:
address points with house numbers, streets, inhabited places (suburbs, villages,
cities, states etc.) and administrative boundaries.
The poi layer selects all point of interest. This includes classic points
of interest like restaurants, shops, hotels but also less obvious features
like recycling bins, guideposts or benches.
The railway layer includes railway infrastructure like tracks.
Note that in Nominatim's standard configuration, only very few railway
features are imported into the database.
The natural layer collects features like rivers, lakes and mountains while
the manmade layer functions as a catch-all for features not covered by the
other layers.
Polygon output
| Parameter | Value | Default |
|---|---|---|
| polygon_geojson | 0 or 1 | 0 |
| polygon_kml | 0 or 1 | 0 |
| polygon_svg | 0 or 1 | 0 |
| polygon_text | 0 or 1 | 0 |
Add the full geometry of the place to the result output. Output formats in GeoJSON, KML, SVG or WKT are supported. Only one of these options can be used at a time.
| Parameter | Value | Default |
|---|---|---|
| polygon_threshold | floating-point number | 0.0 |
When one of the polygon_* outputs is chosen, return a simplified version of the output geometry. The parameter describes the tolerance in degrees with which the geometry may differ from the original geometry. Topology is preserved in the geometry.
Other
| Parameter | Value | Default |
|---|---|---|
| valid email address | unset |
If you are making large numbers of request please include an appropriate email address to identify your requests. See Nominatim's Usage Policy for more details.
| Parameter | Value | Default |
|---|---|---|
| debug | 0 or 1 | 0 |
Output assorted developer debug information. Data on internals of Nominatim's "search loop" logic, and SQL queries. The output is HTML format. This overrides the specified machine readable format.
Examples
<reversegeocode timestamp="Fri, 06 Nov 09 16:33:54 +0000" querystring="...">
<result place_id="1620612" osm_type="node" osm_id="452010817">
135, Pilkington Avenue, Wylde Green, City of Birmingham, West Midlands (county), B72, United Kingdom
</result>
<addressparts>
<house_number>135</house_number>
<road>Pilkington Avenue</road>
<village>Wylde Green</village>
<town>Sutton Coldfield</town>
<city>City of Birmingham</city>
<county>West Midlands (county)</county>
<postcode>B72</postcode>
<country>United Kingdom</country>
<country_code>gb</country_code>
</addressparts>
</reversegeocode>
Example with format=jsonv2
{
"place_id":"134140761",
"licence":"Data © OpenStreetMap contributors, ODbL 1.0. https:\/\/www.openstreetmap.org\/copyright",
"osm_type":"way",
"osm_id":"280940520",
"lat":"-34.4391708",
"lon":"-58.7064573",
"place_rank":"26",
"category":"highway",
"type":"motorway",
"importance":"0.1",
"addresstype":"road",
"display_name":"Autopista Pedro Eugenio Aramburu, El Triángulo, Partido de Malvinas Argentinas, Buenos Aires, 1.619, Argentina",
"name":"Autopista Pedro Eugenio Aramburu",
"address":{
"road":"Autopista Pedro Eugenio Aramburu",
"village":"El Triángulo",
"state_district":"Partido de Malvinas Argentinas",
"state":"Buenos Aires",
"postcode":"1.619",
"country":"Argentina",
"country_code":"ar"
},
"boundingbox":["-34.44159","-34.4370994","-58.7086067","-58.7044712"]
}
Example with format=geojson
{
"type": "FeatureCollection",
"licence": "Data © OpenStreetMap contributors, ODbL 1.0. https://osm.org/copyright",
"features": [
{
"type": "Feature",
"properties": {
"place_id": "18512203",
"osm_type": "node",
"osm_id": "1704756187",
"place_rank": "30",
"category": "place",
"type": "house",
"importance": "0",
"addresstype": "place",
"name": null,
"display_name": "71, Via Guglielmo Marconi, Saragozza-Porto, Bologna, BO, Emilia-Romagna, 40122, Italy",
"address": {
"house_number": "71",
"road": "Via Guglielmo Marconi",
"suburb": "Saragozza-Porto",
"city": "Bologna",
"county": "BO",
"state": "Emilia-Romagna",
"postcode": "40122",
"country": "Italy",
"country_code": "it"
}
},
"bbox": [
11.3397676,
44.5014307,
11.3399676,
44.5016307
],
"geometry": {
"type": "Point",
"coordinates": [
11.3398676,
44.5015307
]
}
}
]
}
Example with format=geocodejson
https://nominatim.openstreetmap.org/reverse?format=geocodejson&lat=60.2299&lon=11.1663
{
"type": "FeatureCollection",
"geocoding": {
"version": "0.1.0",
"attribution": "Data © OpenStreetMap contributors, ODbL 1.0. https://osm.org/copyright",
"licence": "ODbL",
"query": "60.229917843587,11.16630979382"
},
"features": {
"type": "Feature",
"properties": {
"geocoding": {
"place_id": "42700574",
"osm_type": "node",
"osm_id": "3110596255",
"type": "house",
"accuracy": 0,
"label": "1, Løvenbergvegen, Mogreina, Ullensaker, Akershus, 2054, Norway",
"name": null,
"housenumber": "1",
"street": "Løvenbergvegen",
"postcode": "2054",
"county": "Akershus",
"country": "Norway",
"admin": {
"level7": "Ullensaker",
"level4": "Akershus",
"level2": "Norway"
}
}
},
"geometry": {
"type": "Point",
"coordinates": [
11.1658572,
60.2301296
]
}
}
}