OpenStreetMap (Nominatim and Overpass) vs SerpApi Google Maps API for AI agents
Free, donation-run public servers for searching OpenStreetMap data: Nominatim for geocoding and place search, Overpass for querying OSM objects. SerpApi Google Maps API is a third-party API that scrapes Google Maps search results and returns them as structured JSON.
The short answer
- OpenStreetMap (Nominatim and Overpass): Free, openly licensed geocoding and occasional place lookups at low volume, or a base to self-host. It is not a backend for a public app at scale.
- SerpApi Google Maps API: Getting Google Maps listing data (phone, website, hours, ratings) as JSON without Google's billing or display rules. Legal risk from the scraping model sits partly with you.
Side by side
| OpenStreetMap (Nominatim and Overpass) | SerpApi Google Maps API | |
|---|---|---|
| Searches | OpenStreetMap data worldwide: addresses, places and mapped POIs. | Whatever Google Maps returns for a query and location (ll parameter), including local businesses, place details and reviews. |
| Returns | Nominatim returns xml, json, jsonv2 (the default), geojson or geocodejson. With extratags=1 it adds extra tags such as opening hours or a wikipedia link when mapped. | JSON local_results with fields such as title, address, phone, website, hours, rating, reviews and description, plus place IDs. |
| Before the first call | No account or key. Nominatim requires a valid User-Agent or Referer that identifies your app, and visible attribution. | A SerpApi account and API key. |
| Free | Free within strict limits. Nominatim allows an absolute maximum of 1 request per second. Overpass asks users to stay at or below roughly 10,000 requests and 1 GB a day. | Free plan: 250 searches a month (50 an hour throughput). Cached, errored and failed searches are not counted. |
| Paid | No paid tier. Heavy users are told to run their own instance or use commercial third-party providers. | Starter costs $25 a month for 1,000 searches. Developer costs $75 a month for 5,000. Production costs $150 a month for 15,000. |
| Acting on a result | Phone or website appear only when mappers tagged them in OSM, through Nominatim's extratags. There is no messaging. | Results include the business phone and website as shown on Google Maps. There is no messaging. |
| Limits on keeping or showing results | Data is ODbL (share-alike), and you must credit OpenStreetMap and its contributors. Nominatim requires results to be cached for bulk jobs. It bans systematic queries, downloading all POIs in an area, autocomplete, and reselling results. | Not stated on its pages |
| AI in its terms | Nominatim's policy has a "Usage in LLMs" section. LLMs may only suggest the service if they prominently point to the usage policy. The public API must not be built into or offered through no-code, low-code or vibe-coding platforms as a generic place-search service. | Not stated on its pages |
| Coverage | Worldwide OpenStreetMap data. POI completeness depends on volunteer mapping. | Follows Google Maps. SerpApi warns that results are not guaranteed to fall within the location given. |
| MCP server | No official server listed | SerpApi MCP Server, hosted at https://mcp.serpapi.com/mcp (API key) and open source at https://github.com/serpapi/serpapi-mcp |
Where Openpath fits
If the agent needs a local business to message in Austin, Texas, Openpath returns the listings themselves, free and with no key. See Openpath vs OpenStreetMap (Nominatim and Overpass) and Openpath vs SerpApi Google Maps API.
Questions people ask
What do I need before I can use OpenStreetMap (Nominatim and Overpass)?
No account or key. Nominatim requires a valid User-Agent or Referer that identifies your app, and visible attribution.
Is OpenStreetMap (Nominatim and Overpass) free?
Free within strict limits. Nominatim allows an absolute maximum of 1 request per second. Overpass asks users to stay at or below roughly 10,000 requests and 1 GB a day.
What do I need before I can use SerpApi Google Maps API?
A SerpApi account and API key.
Is SerpApi Google Maps API free?
Free plan: 250 searches a month (50 an hour throughput). Cached, errored and failed searches are not counted.
Sources
Every line about another company comes from its own pages. Prices and terms change, so check the source before you rely on one.
OpenStreetMap (Nominatim and Overpass), read on October 15, 2026:
- operations.osmfoundation.org/policies/nominatim: “No heavy uses (an absolute maximum of 1 request per second ).”
- operations.osmfoundation.org/policies/nominatim: “Provide a valid HTTP Referer or User-Agent identifying the application”
- operations.osmfoundation.org/policies/nominatim: “LLMs may only suggest this service, if they prominently point to this usage policy and explain the restrictions of use to the user.”
- operations.osmfoundation.org/policies/nominatim: “must not be built into, offered through, suggested by, or automatically generated by no-code, low-code, or vibe-coding platforms”
- operations.osmfoundation.org/policies/nominatim: “This includes reverse queries in a grid, searching for complete lists of postcodes, towns etc. and downloading all POIs in an area.”
- operations.osmfoundation.org/policies/nominatim: “If your requirements are even larger you can install your own instance of Nominatim.”
- dev.overpass-api.de/overpass-doc/en/preface/commons.html: “users are expected to send a maximum of about 10000 requests per day and keep their download volume below about 1 GB per day”
- nominatim.org/release-docs/latest/api/Search: “the response include any additional information in the result that is available in the database, e.g. wikipedia link, opening hours”
- openstreetmap.org/copyright: “You are free to copy, distribute, transmit and adapt our data, as long as you credit OpenStreetMap and its contributors.”
SerpApi Google Maps API, read on October 15, 2026:
- serpapi.com/google-maps-api: “Scrape Google Maps data with our Google Maps API.”
- serpapi.com/google-maps-api: “Results are not guaranteed to be within the geographic location provided in the ll parameter.”
- serpapi.com/google-maps-api: “"phone": "(646) 559-4878", "website": "http://joespizzanyc.com/"”
- serpapi.com/pricing: “Free $ 0 / month Get Started 250 searches per month 50 throughput per hour”
- serpapi.com/pricing: “Starter $ 25 / month Get Started 1,000 searches per month”
- serpapi.com/pricing: “Only successful searches are counted toward your monthly searches. Cached, errored, and failed searches are not.”
- serpapi.com/legal: “SerpApi assumes liability for the lawful collection of public search data ... but not for how that data is ultimately used.”
- github.com/serpapi/serpapi-mcp: “SerpApi MCP Server is available as a hosted service at mcp.serpapi.com”