GeographyStandardCC-BY-SA-4.0

Nominatim — OpenStreetMap geocoding

Name: Nominatim — OpenStreetMap geocoding
License: CC-BY-SA-4.0

Nominatim is the official geocoding API built on OpenStreetMap data. Provides free-form and structured address → coordinates (geocoding), coordinates → address (reverse geocoding), POI search and OSM-ID lookups — globally, without an API key. Complements Kartverket (the Norwegian primary source) with global coverage and place search. ODbL licence, max 1 req/s against the public server (results are cached).

—

Data volume

Daily

Updates

MCP tools

Example response — /connectors/nominatim/search

{
  "data": "..."
}

MCP integration

Available MCP tools

nominatim.geocode

nominatim.lookup

nominatim.reverse

nominatim.search

Configuration for Claude Desktop / Cursor

{
  "mcpServers": {
    "nominatim": {
      "url": "https://data.ketl.no/mcp/nominatim",
      "headers": {
        "Authorization": "Bearer $KETL_API_KEY"
      }
    }
  }
}

Analysis apps that use this source

Ready-made tools built on Nominatim — OpenStreetMap geocoding data. Use them directly in the browser, or wire the same data into your own analysis via the API below.

Real estate

Cadastral and area analysis for a property — cadastral information, price history and adjacent nature and area data from Kartverket and Naturbase. For plain address geocoding, use Adressesøk.

Weather and climate

Weather forecasts, observations and climate data for all of Norway.

Geocoding (OpenStreetMap)

Global free-form geocoding via OpenStreetMap Nominatim — forward (address → coordinates) and reverse (coordinates → address). Complementary to Kartverket address search for Norwegian addresses.

Ground conditions

Geotechnical boreholes and groundwater wells from NGU's national database NADAG — address lookup via Nominatim shows registered ground investigations within a chosen radius. Relevant as a first step in site assessment and property due diligence.

API endpoints

GET

/search

Fri-form adresse-/stedsøk

q required: Fritekst-adressesøk q=Karl Johans gate, Oslo
country optional: Begrens til ISO-3166-1 alpha-2 landkode(r), kommaseparert country=no
countrycodes optional: Alias for `country` (Nominatims eget navn). `country` vinner hvis begge er gitt. countrycodes=no
limit optional: Maks antall treff limit=10
viewbox optional: Prioriter/begrens til bounding box: x1,y1,x2,y2 (lon/lat)
bounded optional: Når true sammen med viewbox: kun treff strengt innenfor boksen

Show curl example

# GET https://data.ketl.no/api/connectors/nominatim/search?q=Karl%20Johans%20gate%2C%20Oslo
curl \
  -H "Accept: application/json" \
  "https://data.ketl.no/api/connectors/nominatim/search?q=Karl%20Johans%20gate%2C%20Oslo"

Authenticated call — add one of these headers: x-api-key: ketl_… · Authorization: Bearer … — See the full reference in the documentation.

GET

/geocode

Strukturert geokoding (street/city/country)

street optional: Gate (minst ett av street/city/county/state/country/postalcode) street=Karl Johans gate 1
city optional: By city=Oslo
county optional: Fylke. NORSKE fylker slås opp her — ikke via `state` county=Oslo
state optional: Delstat/region. OSM fører IKKE norsk administrativ geografi som `state` (Oslo/Vestland gir 0 treff, målt 2026-08-20) — bruk `county` for norske fylker. Eksempelet er derfor tysk state=Bayern
country optional: Land country=Norway
postalcode optional: Postnummer postalcode=0154
limit optional: Maks antall treff limit=5

Show curl example

# GET https://data.ketl.no/api/connectors/nominatim/geocode
curl \
  -H "Accept: application/json" \
  "https://data.ketl.no/api/connectors/nominatim/geocode"

Authenticated call — add one of these headers: x-api-key: ketl_… · Authorization: Bearer … — See the full reference in the documentation.

GET

/reverse

Omvendt geokoding (koordinat → adresse)

lat required: Breddegrad (WGS84) lat=59.913
lon required: Lengdegrad (WGS84) lon=10.752
zoom optional: OSM-detaljnivå for treffet (0 = land, 10 = by, 18 = bygning). Utelat for Nominatims default. zoom=18

Show curl example

# GET https://data.ketl.no/api/connectors/nominatim/reverse?lat=59.913&lon=10.752
curl \
  -H "Accept: application/json" \
  "https://data.ketl.no/api/connectors/nominatim/reverse?lat=59.913&lon=10.752"

Authenticated call — add one of these headers: x-api-key: ketl_… · Authorization: Bearer … — See the full reference in the documentation.

GET

/lookup

Oppslag på OSM-ID-er

osm_ids required: Kommaseparert liste OSM-IDer (N/W/R-prefiks) osm_ids=R2978650

Show curl example

# GET https://data.ketl.no/api/connectors/nominatim/lookup?osm_ids=R2978650
curl \
  -H "Accept: application/json" \
  "https://data.ketl.no/api/connectors/nominatim/lookup?osm_ids=R2978650"

Authenticated call — add one of these headers: x-api-key: ketl_… · Authorization: Bearer … — See the full reference in the documentation.

Access and pricing

Nominatim — OpenStreetMap geocoding is openly available — create an account to get started.

adressegeocodingkartopenstreetmapglobalpoikoordinat