Check the record, not the prose
The answer names the place, region, country and format, and links to a page a person can inspect. That is easier to trust than a paragraph that sounds confident.
COMPARE · POSTCODEDOG VS CHATGPT
PostcodeDog vs ChatGPT
A checkable postal record, not a chat answer.
ChatGPT is a general assistant. PostcodeDog is a postal lookup that returns a place, region and format you can check, and exposes the same lookup to AI clients through MCP.
SIDE BY SIDE
What changes with PostcodeDog
| Capability | UsPostcodeDog | ChatGPT | Why it matters |
|---|---|---|---|
| Output | Place, region and format from a postal record | A conversational answer | A checkable record is easier to verify before a label. |
| Source | GeoNames postal data, attributed on the data page | Model knowledge and browsing | The data page and place page are traceable. |
| Batch | Paste up to 50 rows, review, export CSV | One conversation at a time | Clear a label queue in one pass. |
| Agents | Built-in MCP server and JSON API | Tools and connectors, where supported | Wire the lookup into the assistant instead of retyping. |
| Languages | 13 interface languages | Assistant languages | Local teams can work in their own language. |
WHERE POSTCODEDOG WINS
A postal tool the assistant can call.
Batch before the label run
Fifty rows per run in the browser, with valid, ambiguous and missing statuses and a CSV export. No prompt engineering required.
Give AI clients a real tool
MCP-capable clients can call lookup, search, validation and address parsing directly, so the model does not have to remember postal codes.
TRY IT
Try the difference
Paste a full address, a city or a post code. Country and format are detected.
Free. No account, no API key.THE LOOP
Paste → resolve → verify
The same three steps work whether the address is a US ZIP, a UK outcode or a Japanese 〒.
- 01
Paste what you have
A full address, a city, or just a code. The parser accepts the whole line.
- 02
Confirm the place and format
Country, region and post code format are shown together, with nearby codes for a second option.
- 03
Send it to the label
Copy the verified code or export the batch. Platform and carrier pages keep local rules in view.
About
About ChatGPT
ChatGPT is a general-purpose AI assistant from OpenAI, used for writing, research and problem solving. It can discuss postal codes, but it is not a dedicated postal dataset.
PostcodeDog returns structured place records for 82 countries and can be called by MCP-capable assistants.
When PostcodeDog is the better fit
- 01You need a postal answer you can verify, not a chat reply.
- 02You are clearing a batch before a label run.
- 03You want to connect a postal lookup to an AI client.
- 04Your team works across several languages.
Is PostcodeDog an AI?
No. It is a postal lookup with structured records, a batch page, a JSON API and an MCP server. AI clients can call it as a tool.
Can ChatGPT use PostcodeDog?
MCP-capable clients can connect to /mcp; the install guide has setup steps for the supported clients. The JSON API works from any stack.
Is PostcodeDog free?
Yes. Lookups, batch checks, the JSON API and the MCP server are free and need no account.
Can I use it in an AI agent?
Yes. The MCP server is at /mcp, and the JSON API is free to call.
Compare
Give the assistant a real lookup.
Try a code in the browser, then connect the same lookup through MCP.