pyproj

library3.7.2pypypi✓ verified 27d ago

pyproj is a Python interface to PROJ, a powerful C library for cartographic projections and coordinate transformations. It enables precise coordinate reference system (CRS) operations, geodesic computations, and transformation between different spatial reference systems with high accuracy and comprehensive EPSG support. The library is actively maintained with frequent releases, currently at version 3.7.2.

data serialization

pip install pyproj

github ↗package ↗homepage ↗docs ↗changelog ↗

INSTALL

IMPORT

SIG · PYPROJ

pyproj

datapythonv3.7.2

Install

1.9s avg

Import

234ms

Disk

47MB

Pass rate

9/ 10

Env Coverage9 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v3.7.1 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

glibc

py 3.10

✓ —

✓ 1.9s

py 3.11

✓ —

✓ 2s

py 3.12

✓ —

✓ 1.8s

py 3.13

✓ —

✓ 1.8s

py 3.9

✕ build_error

✓ 2.2s

47MB installed

● package 47MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

CRS

✓ from pyproj import CRS

Used for defining Coordinate Reference Systems.

Transformer

✓ from pyproj import Transformer

The modern and recommended class for performing coordinate transformations.

Proj

✓ from pyproj import Proj

✗ from pyproj import Proj; p = Proj(init='epsg:4326')

While still available for backward compatibility, `pyproj.Proj` is a legacy interface. `pyproj.Transformer` is the recommended and more robust approach for transformations, especially for `CRS` to `CRS` conversions. Initializing with `init` is deprecated.

Geod

✓ from pyproj import Geod

Used for geodesic calculations (e.g., distances, areas, forward/inverse problems on an ellipsoid).

This quickstart demonstrates how to perform a basic coordinate transformation from WGS84 geographic coordinates (longitude, latitude) to UTM Zone 33N projected coordinates (easting, northing) using `pyproj.CRS` to define the coordinate systems and `pyproj.Transformer` for the transformation. The `always_xy=True` parameter ensures a consistent (x, y) or (longitude, latitude) axis order.

from pyproj import CRS, Transformer # Define source and target Coordinate Reference Systems (CRSs) wgs84 = CRS('EPSG:4326') # WGS84 Geographic CRS (longitude, latitude) utm_zone_33n = CRS('EPSG:32633') # UTM Zone 33N Projected CRS (easting, northing) # Create a transformer, ensuring consistent axis order (x, y / lon, lat) transformer = Transformer.from_crs(wgs84, utm_zone_33n, always_xy=True) # Define a point in WGS84 (longitude, latitude) lon, lat = 10.0, 60.0 # Transform the point x, y = transformer.transform(lon, lat) print(f"Original WGS84 (lon, lat): ({lon}, {lat})") print(f"Transformed UTM Zone 33N (easting, northing): ({x:.2f}, {y:.2f})") # Transform multiple points points_wgs84 = [(10.0, 60.0), (11.0, 61.0), (12.0, 62.0)] transformed_points_utm = list(transformer.itransform(points_wgs84)) print(f"Transformed multiple points: {transformed_points_utm}")

Debug

Known issues

breakingMinimum Python version required for pyproj has increased significantly in recent 3.x releases. For pyproj 3.7.2, Python 3.11 or newer is required.

fix

Upgrade your Python environment to 3.11 or newer, or use an older pyproj version compatible with your Python version. (e.g., pyproj 3.6.0 for Python 3.9+, pyproj 3.7.0 for Python 3.10+).

affects: 3.7.2+

breakingMinimum PROJ C library version required for pyproj has increased. For pyproj 3.7.2, PROJ 9.4 or newer is required.

fix

Ensure your system's PROJ installation meets the minimum requirement (PROJ 9.4+). If installing via pip, wheels often bundle PROJ, but if building from source or using conda, verify your PROJ version.

affects: 3.7.2+

deprecatedThe `pyproj.Proj` class is considered a legacy interface. Its `init` keyword for initialization is deprecated.

fix

Migrate to `pyproj.CRS` for defining Coordinate Reference Systems and `pyproj.Transformer` for performing transformations. For example, instead of `Proj(init='epsg:4326')`, use `CRS('EPSG:4326')` and `Transformer.from_crs()`.

affects: 3.0.0+

gotchapyproj 3.x wheels no longer include transformation grids by default. These grids are crucial for certain high-accuracy datum transformations (e.g., NAD27 to NAD83).

fix

You may need to manually manage PROJ's data directory or install transformation grid packages separately. Consult the pyproj documentation on 'Transformation Grids' for guidance.

affects: 3.0.0+

gotchaWhen performing transformations, the axis order (e.g., longitude/latitude vs. latitude/longitude, or easting/northing vs. northing/easting) can be a source of confusion. By default, PROJ might use different axis orders based on CRS definition.

fix

Always use `always_xy=True` when creating a `Transformer` instance to ensure consistent (x, y) or (longitude, latitude) input and output order, which aligns with common GIS conventions.

affects: 2.2.0+

breakingThe default value for `return_back_azimuth` in `fwd_intermediate` and `inv_intermediate` methods of `pyproj.Geod` changed from `False` to `True` to match `fwd` and `inv` methods.

fix

If your code relies on the previous default behavior, explicitly set `return_back_azimuth=False` when calling `fwd_intermediate` or `inv_intermediate`.

affects: 3.5.0+

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'pyproj'

The pyproj library is not installed in your current Python environment.

fix

pip install pyproj

DeprecationWarning: `transform` is deprecated. Use `pyproj.Transformer.from_crs` instead.

The direct `pyproj.transform()` function is deprecated in pyproj 2.x and 3.x; the recommended approach is to use `pyproj.Transformer.from_crs()` for better control and performance.

fix

Replace `pyproj.transform(crs_from, crs_to, x, y)` with `transformer = pyproj.Transformer.from_crs(crs_from, crs_to, always_xy=True); x2, y2 = transformer.transform(x, y)`.

pyproj.exceptions.CRSError: Invalid projection string: +init=epsg:4326

The `+init=` syntax for defining a CRS is deprecated and no longer directly supported by the underlying PROJ library in modern `pyproj` versions, leading to an invalid string error.

fix

Replace deprecated `+init=epsg:XXXX` with the modern `EPSG:XXXX` string when defining CRSs (e.g., `pyproj.CRS('EPSG:4326')`).

NameError: name 'Proj' is not defined

In pyproj versions 2.x and later, the `Proj` class is not automatically imported into the top-level `pyproj` namespace and its functionality is largely superseded by `CRS` and `Transformer`.

fix

For CRS definitions, use `pyproj.CRS()`. For transformations, use `pyproj.Transformer.from_crs()`. If `Proj` is strictly needed, import it explicitly with `from pyproj import Proj`.

Upgrade

Version history

3.7.2latest on PyPI · released Aug 14, 2025

Audit

Dependencies

PythonrequiredMinimum supported Python version is 3.11 for pyproj 3.7.2.

PROJrequiredpyproj is a wrapper around the PROJ C library; minimum supported PROJ version is 9.4 for pyproj 3.7.2.

Transformation Gridsoptionalpyproj 3+ wheels do not include transformation grids; these may need to be obtained separately for certain high-accuracy transformations.

Agent activity

14 hits · last 30 days

node

Resources

githubhttps://github.com/pyproj4/pyproj ↗

packagehttps://pypi.org/project/pyproj/ ↗

homepagehttps://pyproj4.github.io/pyproj/ ↗

docshttps://pyproj4.github.io/pyproj/ ↗

changeloghttps://pyproj4.github.io/pyproj/stable/history.html ↗