Geographic Region Codes Explained: NUTS, FIPS, ISO 3166 & More
A complete guide to statistical region codes used in data visualization – NUTS, FIPS, ISO 3166 and global standards explained with examples.

A complete guide to statistical region codes used in data visualization – NUTS, FIPS, ISO 3166 and global standards explained with examples.

Anyone who has worked with geographic data has run into the same problem: your dataset says "DE21" or "06037" or "US-CA", and you need to put that on a map. These aren't random strings — they're standardized region codes, and understanding them is the difference between a clean visualization and hours of debugging mismatched data.
This guide covers the major geographic coding systems used in data analysis, journalism, and policy research. We explain what each standard covers, how the codes are structured, and where they apply — so you can match your data to the right boundaries.