Openstreetmap Nominatim Geocoding API

Name: Nominatim Geocoding API
Brand: Nominatim Geocoding API
Availability: InStock

✓ Official Vendor SpecMaps GeolocationGeocodingnone4 EndpointsREST

For Agents

Geocode addresses to coordinates, reverse-geocode coordinates to addresses, and look up specific OpenStreetMap objects worldwide.

Install Jentic One Beta

Connect the Nominatim Geocoding API to your agent

Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Nominatim Geocoding API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.

Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.

Step 1: Jentic One Host machine

# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh

Step 2: Agent machine

# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register       # connects your agent to your Jentic One instance

Jentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.

Capabilities

What an agent can do with Nominatim Geocoding API.

Geocode an address or place name to latitude and longitude using /search

Reverse-geocode a lat/lng pair to the nearest address with /reverse

Look up specific OpenStreetMap objects by OSM ID using /lookup

GET STARTED

Start building with Nominatim Geocoding API

Explore with Jentic

View OpenAPI Document

Use Cases

Patterns agents use Nominatim Geocoding API for, with concrete tasks.

★ Free Worldwide Address Geocoding

Convert user-entered addresses into latitude and longitude for storage, mapping, or distance calculations. Nominatim's /search endpoint accepts free-form queries or structured fields (street, city, postalcode, country) and returns scored matches with bounding boxes. It covers every country mapped in OpenStreetMap, making it useful for projects that need global coverage without per-request fees.

Call GET /search with q='Brandenburg Gate, Berlin' and format=json and return the first result's lat and lon

Reverse Geocoding for Mobile Check-ins

Mobile applications that capture a user's GPS coordinates can call /reverse to display the nearest address or place name in the UI. Nominatim returns a structured address with hierarchy (road, suburb, city, country) plus a formatted display_name string suitable for direct rendering. This is common in delivery, ride-share, and field-service apps where the device knows the coordinates but the user wants a human-readable location.

Call GET /reverse with lat=37.7749, lon=-122.4194, format=json and return the display_name field

OSM Object Lookup for Map Editors

When working with OpenStreetMap data dumps or building tools on top of OSM, you often need to resolve a list of OSM IDs to human-readable names and locations. The /lookup endpoint accepts up to 50 OSM type+ID pairs in a single request and returns enriched objects. This is more efficient than running separate /search calls and preserves OSM's canonical relationships between nodes, ways, and relations.

Call GET /lookup with osm_ids=N240109189,W43147938,R558775 and format=json to enrich a list of OSM references

AI Agent Location Assistant

An AI agent answering 'where is X' or 'what's near coordinate Y' can use Nominatim through Jentic without managing rate-limit headers, user-agent strings, or self-hosting. Jentic resolves the natural-language intent into the right /search or /reverse call and applies the public instance's usage policy. For higher volume the agent can be repointed at a self-hosted Nominatim with no agent-side change.

Through Jentic, search 'geocode an address' and execute against q='Eiffel Tower, Paris' to return coordinates

Key Endpoints

4 endpoints — nominatim is the official geocoding service for openstreetmap data.

METHOD

PATH

DESCRIPTION

GET

/search

Forward geocode an address or place name

GET

/reverse

Reverse geocode coordinates to an address

GET

/lookup

Look up specific OSM objects by ID

GET

/status

Check Nominatim server status

GET

/search

Forward geocode an address or place name

GET

/reverse

Reverse geocode coordinates to an address

GET

/lookup

Look up specific OSM objects by ID

GET

/status

Check Nominatim server status

Why Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

Nominatim needs no key, so no credential is stored for this API. Jentic still routes each call through the same audited execution path used for authenticated APIs, and nothing secret ever enters the agent's prompt, logs, or context.

Intent-based discovery

Agents search Jentic by intent such as 'geocode an address' or 'reverse geocode coordinates', and Jentic returns the matching Nominatim operation with its parameter schema so the agent calls the right endpoint without browsing the reference docs.

Time to first call

FAQs

Specific to using Nominatim Geocoding API through Jentic.

What authentication does the Nominatim Geocoding API use?

The public Nominatim instance does not require an API key, but it does require a meaningful User-Agent header identifying your application per the OpenStreetMap usage policy. Through Jentic, the User-Agent is set automatically based on the agent's identity.

Can I geocode multiple addresses in one request with Nominatim?

The /search endpoint takes one query at a time. For batch use, fan out parallel requests within the rate limit (1 request/sec on the public instance) or use /lookup which accepts up to 50 OSM IDs in a single call.

What are the rate limits for the Nominatim Geocoding API?

The public nominatim.openstreetmap.org instance allows at most 1 request per second per IP and prohibits heavy usage. For higher volume you must self-host Nominatim or use a paid mirror; the API surface stays identical.

How do I reverse-geocode a coordinate through Jentic?

Search Jentic for 'reverse geocode coordinates', load the GET /reverse schema, and execute with lat, lon, and format=json. Jentic returns the structured address response from Nominatim including the display_name string.

Does Nominatim support routing or directions?

No - Nominatim is geocoding only. For routing on OpenStreetMap data use OSRM, GraphHopper, or Valhalla. For places search and points of interest, /search supports it but is not optimized for ranked POI discovery; consider Overpass API for richer POI queries.

How fresh is the data in the Nominatim Geocoding API?

Public Nominatim updates from the OSM minutely diff stream, so most edits are reflected within minutes to hours. The /status endpoint reports the current data timestamp so you can confirm the freshness window before relying on a query.

Can I limit what my agent is allowed to do with the Nominatim Geocoding API?

Yes. Because you run Jentic One self-hosted, your own rules decide which Nominatim operations the agent may call. Since Nominatim is read-only geocoding with no credential to store, scoping is by operation: you can allow only search and reverse while leaving lookup and status unavailable, so the agent can geocode addresses and coordinates but nothing more. Every operation the agent can reach is one you chose to permit.