# Address to ZIP (addresstozip.jp)

Searches Japanese addresses and returns their postal codes through an API, with an MCP server for AI agents.

- Atlas card: https://inite.ai/en/atlas/addresstozip.jp
- Site: https://addresstozip.jp
- For: Developers and AI agent builders who need Japanese address-to-postal-code lookup in their apps or tools.
- Categories: dev
- Use 0/100 · alive 100/100

## Used for

- look up postal codes from Japanese addresses via API
- let AI assistants search addresses through MCP
- convert CSV lists of Japanese addresses to postal codes

## Price

Not read yet.

## For developers

- OpenAPI: https://addresstozip.jp/openapi.json (3 paths)
- API docs: https://addresstozip.jp/api
- MCP server: jp.addresstozip/address-to-zip (namespace; open on 2026-10-20, 2 tools)
- Status page: https://stats.uptimerobot.com/EBFohWGuoO
- Read 2026-10-20

## MCP server, measured daily

Server: https://addresstozip.jp/mcp, checked every day since 2026-10-20 (1 checks).

- Answered: measuring, 1 daily checks so far
- Median first answer: 178 ms
- Sign-in: none
- Context its tool definitions take: about 314 tokens (2 tools)
- Tool definitions: B, 83/100
- Failing "annotations": 2 of 2 tools
- Method: https://inite.ai/en/atlas/mcp/report

## Your data

- Certifications stated: none
- Read 2026-10-20

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Source: INITE Atlas, https://inite.ai/en/atlas/addresstozip.jp. JSON: https://inite.ai/api/atlas/addresstozip.jp. MCP: https://inite.ai/api/mcp (atlas_lookup).