NANP Area Code Locator

Reverse-geocode latitude/longitude to NANP telephone area codes. Works offline; ships a compact Parquet of polygons.

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✨ Features

• 🔎 Reverse-geocode (lat, lon) → area code(s)
• ⚡ Fast local lookups (vectorized GeoPandas + spatial index)
• 🪪 NANP coverage (US, Canada, participating Caribbean)
• 🧳 Zero setup — packaged Parquet data included (~29 MB)
• 🧭 CRS handled automatically (WGS84 in / projected out as needed)
• 🧵 Simple API & CLI (lookup() and area-code-lookup)

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📦 Install

pip install area-code-locator

# From source:
git clone https://github.com/Eat-A-Fish/area-code-locator.git
cd area-code-locator
pip install -e .

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🚀 Quickstart

from area_code_locator import lookup, batch_lookup

# Single point (returns all matching/overlay codes by default)
codes = lookup(40.7128, -74.0060)      # NYC
print(codes)                           # -> ['212', '646', '917', ...]

# First/primary only
code = lookup(34.0522, -118.2437, return_all=False)  # LA
print(code)                              # -> '213'

# Batch
points = [(40.7128, -74.0060), (41.8781, -87.6298)]
print(batch_lookup(points))              # -> [['212', ...], ['312', ...]]

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🖥️ CLI

area-code-lookup --lat 40.7128 --lon -74.0060
# -> 917

area-code-lookup --lat 40.7128 --lon -74.0060 --all
# -> ["212", "646", "917", ...]

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🧪 API

lookup(lat: float, lon: float, return_all: bool = True) -> Union[str, List[str]]
batch_lookup(points: List[Tuple[float, float]], return_all: bool = True) -> List[Union[str, List[str]]]

• return_all=True → all matching/overlay area codes
• return_all=False → first/primary area code

Advanced

from area_code_locator import AreaCodeLocator

loc = AreaCodeLocator()                       # uses bundled data
loc_custom = AreaCodeLocator("path/to/area-codes.parquet")
loc.lookup(40.7128, -74.0060, return_all=True)

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🗺️ Data

The package includes a preprocessed Parquet file of area-code polygons, so no setup is required.

Using your own data:

• Parquet with a polygon geometry column
• An area-code column named one of: area_code, areacode, npa, or code
• CRS: EPSG:4326 (WGS84)

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🛠️ Development

pip install -e ".[dev]"
pytest

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🙏 Acknowledgments

Area-code boundaries derived from public NANP datasets (e.g., projects compiling NANP polygons). Thanks to the open geospatial community for GeoPandas/Shapely/PyProj.

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📄 License

MIT © Area Code Locator Contributors