README.md

metadata

license: cc-by-4.0
pretty_name: GeoNames Postal Codes (Parquet)
tags:
  - geospatial
  - postal-codes
  - pincode
  - geocoding
  - geonames
size_categories:
  - 1M<n<10M
configs:
  - config_name: default
    data_files: postal_codes.parquet

GeoNames Postal Codes — Parquet

The GeoNames postal code dataset (allCountries.txt) converted to a single sorted, zstd-compressed Parquet file. It is used as a postcode → lat/lon lookup table for joining tabular locations onto gridded weather data (e.g. ERA5 Zarr) in zarr-datafusion.

Rows	1,826,904 (one row per place, not per postcode)
Distinct (country_code, postal_code)	1,080,715
Countries	121
File	postal_codes.parquet, ~19 MB, zstd(3), sorted by country_code, postal_code, place_name
Source snapshot	GeoNames export of 2026-09-22

Schema

column	type	nullable	notes
country_code	string	no	ISO 3166-1 alpha-2
postal_code	string	no	text — many countries use letters (EC1A, 100-0001)
place_name	string	yes	locality / post office
admin_name1 / admin_code1	string	yes	state / province
admin_name2 / admin_code2	string	yes	county / district
admin_name3 / admin_code3	string	yes	community / sub-district
latitude, longitude	float64	no	WGS84 decimal degrees
accuracy	int8	yes	1 = estimated, 4 = GeoNames place id, 6 = centroid of addresses or shape

Caveats

• One row per place. A postcode can have many rows (Delhi 110001 has 21); collapse to one point per (country_code, postal_code) before joining.
• accuracy describes the method, not the error. Countries without published postal geometry are geocoded by place name. India, for example, has no accuracy-6 rows, and over 100 Bengaluru 560xxx pincodes share one fallback district point ~28 km north of the city centre — including rows marked 4.
• UK, Canada and the Netherlands are outward/short codes only here; GeoNames publishes full codes separately (GB_full, CA_full, NL_full), not included.

Usage

Direct HTTPS (supports range requests):

https://huggingface.co/datasets/Stratoscale/GeoNamesPincode/resolve/main/postal_codes.parquet

import duckdb
duckdb.sql("""
  SELECT * FROM 'hf://datasets/Stratoscale/GeoNamesPincode/postal_codes.parquet'
  WHERE country_code = 'IN' AND postal_code = '110001'
""")

Reproduce

curl -O https://download.geonames.org/export/zip/allCountries.zip
unzip allCountries.zip allCountries.txt
zarr-cli cookbook/pincode-lookup/build_postcodes.sql

License and attribution

Licensed under CC BY 4.0, the license of the source data. Contains data from GeoNames (© GeoNames, CC BY 4.0). The data is provided "as is" without warranty of accuracy, timeliness or completeness. Changes from the source: converted from TSV to Parquet, typed columns, sorted; no rows added, removed or modified.