Start with the address in front of you
Paste a Chinese or English address. PostcodeDog detects the country, city and format and returns the matching places, without navigating a province-by-province directory.
COMPARE · POSTCODEDOG VS IP138
PostcodeDog vs IP138 邮编查询
A postal-first lookup for 82 countries, not a general query portal.
IP138 is a Chinese query portal with a national postal-code directory. PostcodeDog is built for the foreign-address moment: paste an address in Chinese or English, detect the country and format, and check it without leaving the page.
SIDE BY SIDE
What changes with PostcodeDog
| Capability | UsPostcodeDog | IP138 邮编查询 | Why it matters |
|---|---|---|---|
| Coverage | 82 countries in one lookup | Chinese postal codes | The address is often outside China. |
| Focus | Postal-first lookup and format check | General query portal | Fewer distractions between the question and the answer. |
| Input | Paste an address, city or code; country and format detected | Browse Chinese postal code lists | Use the text the customer already sent. |
| Batch | Paste up to 50 rows, review, export CSV | One lookup at a time | Clear a label queue in one pass. |
| Languages | 13 interface languages | Chinese | Global teams can work in their own language. |
WHERE POSTCODEDOG WINS
Built for the foreign address, not the domestic directory.
Check a whole label queue
Fifty rows per run in the browser, with valid, ambiguous and missing statuses and a CSV export. No account and no payment step.
Give agents the same lookup
The free MCP server exposes lookup, search and validation to Claude, Cursor and other clients; the JSON API covers checkout and internal tools.
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 IP138 邮编查询
IP138 (ip138.com) is a Chinese online query portal covering IP addresses, phone numbers, postal codes and more. Its postal section lists Chinese postal codes by province, city and district.
PostcodeDog is a postal-first lookup for 82 countries with 13 languages, batch, API and MCP.
When PostcodeDog is the better fit
- 01You fill foreign addresses every day, not only Chinese ones.
- 02You want a postal-first tool instead of a general query portal.
- 03You need a free batch check before a label run.
- 04Your team works in Chinese, English or another of the 13 languages.
Is IP138 China-only?
IP138’s postal directory focuses on Chinese postal codes. PostcodeDog covers China alongside 81 other countries, so the same lookup works for foreign destinations.
Can PostcodeDog handle Chinese addresses?
Yes. The interface is available in Simplified and Traditional Chinese, and Chinese city names are accepted in the lookup.
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
Check a foreign code in one box.
Paste an address or try 90210, SW1A or 100-0001. No signup needed.