# RingFence

> RingFence finds every postal code and every town within a radius of a postal code, town, or latitude/longitude, worldwide, in miles or kilometers. Results export to CSV or Excel, come back from a REST API as JSON, CSV, or a plain postal-code list, and are available to AI agents as a remote MCP server.

Key facts:

- Coverage: postal codes for 120+ countries and towns/cities for 250 countries and territories (about 1.8 million postal codes and 236,000 populated places), from GeoNames.
- Towns are returned alongside postal codes, including towns in countries without postal data.
- Inputs: postal code (e.g. 02139, SW1A, 10115), town name with optional state or country ("Springfield, IL"), or coordinates. Ambiguous inputs return candidates instead of a guess.
- Town names can be typed in Latin, Cyrillic, or Korean script (Москва finds Moscow, 서울 finds Seoul), with or without accents (Zurich, Zürich, and Zuerich all match).
- Radius: up to 150 in the chosen unit (150 miles or 150 km), inclusive of the boundary. Distance is great-circle (haversine) distance to each postal code's or town's center point.
- Output: up to 50,000 rows per search with postal code, distance, town, state/region, county, country, latitude, longitude.
- Export: CSV, Excel (.xlsx), or a copyable postal-code list in the web app.
- REST API: GET or POST https://ringfence.zinglab.com/api/v1/search with "Authorization: Bearer rf_live_...". format=json (default), csv, or zip_list. OpenAPI spec: https://ringfence.zinglab.com/openapi.yaml
- MCP: remote MCP endpoint https://ringfence.zinglab.com/mcp (Bearer API key). Tools: radius_search, resolve_location.
- API keys: one active key per account, created and rotated in the web app.
- Price: $99/month flat subscription with no per-search charges. Fair-use rate limits apply to API and MCP access.

## Product pages

- [Give your AI agent a real radius search tool.](https://ringfence.zinglab.com/ai-agents/): RingFence is a remote MCP server that lets AI agents list every postal code and town within a radius, worldwide. Tools: radius_search and resolve_location. Works with any MCP client.
- [Postal codes in 120+ countries. Towns in 250.](https://ringfence.zinglab.com/coverage/): RingFence covers about 1.8 million postal codes in 120+ countries and 236,000 towns in 250 countries and territories, including all 50 US states, Canada, Mexico, the UK, and 26 of 27 EU member states.
- [A radius search API that returns postal codes and towns worldwide.](https://ringfence.zinglab.com/developers/): RingFence's REST API returns every postal code and town within a radius as JSON, CSV, or a plain code list. Worldwide coverage, great-circle distances, Bearer API keys. OpenAPI spec included.
- [Every postal code and town inside any radius, anywhere in the world.](https://ringfence.zinglab.com/features/): RingFence returns every postal code and town within a radius, in 120+ countries for postal codes and 250 for towns. Export to CSV or Excel, call the REST API, or give AI agents the MCP tool.
- [Every postal code and town inside your radius. Anywhere in the world.](https://ringfence.zinglab.com/): RingFence lists every postal code and town within a radius of any postal code or town, in 120+ countries. Export to CSV or Excel, automate with the REST API, or give AI agents the MCP tool. $99/month.
- [One plan. Everything included.](https://ringfence.zinglab.com/pricing/): RingFence costs $99/month and includes worldwide postal code and town radius search, CSV and Excel export, the REST API, and the MCP server for AI agents. No per-search charges.
- [Radius lists for every team that sells to a place.](https://ringfence.zinglab.com/use-cases/): How marketing, sales, franchise, recruiting, real estate, and operations teams use RingFence to list every postal code and town within a radius, then export it or automate it.

## Developer resources

- [OpenAPI specification](https://ringfence.zinglab.com/openapi.yaml): REST API reference
- [API guide](https://ringfence.zinglab.com/developers/): authentication, parameters, examples
- [MCP for AI agents](https://ringfence.zinglab.com/ai-agents/): connecting an agent to the radius_search tool

## Blog

- [Why your radius list needs towns, not just ZIP codes](https://ringfence.zinglab.com/blog/towns-not-just-zip-codes/): ZIP codes tell machines where to deliver; town names tell people where they live. Here's why a radius list with both converts better, and how RingFence returns them together.
- [RingFence vs. ZIP code radius tools: a head-to-head comparison](https://ringfence.zinglab.com/blog/ringfence-vs-zip-code-radius-tools/): How RingFence compares to free radius maps, US-only ZIP radius APIs, GIS software, DIY databases, and asking a chatbot, on coverage, towns, export, API access, and AI agent support.
- [Field marketers: radius geotag lists for Marketo, Pardot, Eloqua, HubSpot, and Inflection](https://ringfence.zinglab.com/blog/field-marketing-geotag-lists-for-marketing-automation/): How field marketers use RingFence to build postal code and town lists for any event or territory radius, then target those contacts in Marketo, Salesforce Account Engagement (Pardot), Oracle Eloqua, HubSpot, and Inflection.