portpicker
A library to choose unique available network ports.
Decision gist · record as of 2026-08-14
Yes, for test automation and development. The package is stable and has no known vulnerabilities, with low install friction. However, the repository is archived and unmaintained—if you encounter a bug or need a feature, you will need to fork or find an alternative. For production port coordination at scale, evaluate the included port server carefully or consider running it in a controlled test environment first.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Requires Python 3.6 or later.
- Race condition exists between port selection and binding; for production use, the documentation recommends running a port server daemon (included) and setting PORTSERVER_ADDRESS=@unittest-portserver.
- Low friction install with a single runtime dependency (psutil).
License · maintenance · safety
Apache 2.0 (permissive) — Licensed under Apache 2.0 (permissive), so you can use, modify, and distribute it freely in commercial and private projects without restriction.
last release 2023-08-15 (1095 days) · last repo commit 2023-08-15 · 149 stars · archived
0 known vulnerabilities (OSV.dev, 2026-08-14) · 3,396,179 downloads/mo, #2,636 on PyPI
Alternatives
Verify before relying
import portpicker
test_port = portpicker.pick_unused_port()
# Or from command line:
# python3 -m portpicker $$- Whether the port server daemon included in the package is production-ready or still considered experimental.
- Current state of the repository and whether critical bug fixes are still accepted despite archival status.
- Whether the race condition between picking a port and binding to it remains acceptable for modern test workloads.
What it is and what it does
Portpicker is a utility for finding an unused network port on the local host. It exposes a simple `pick_unused_port()` function that returns an available port number, and can also be invoked from the command line or as a Python module. The package is designed primarily for test automation, where you need to dynamically allocate ports without conflicts.
The library depends on psutil to check port availability. The documentation acknowledges a fundamental race condition: a port may be selected as free but claimed by another process before your code binds to it. For single-threaded test runs this is usually acceptable, but for loaded test hosts running many tests concurrently, the package includes an optional port server daemon that coordinates port allocation across all processes on the host, eliminating the race condition.
Use it for
- Allocate a unique port dynamically in unit tests that start temporary servers.
- Obtain an available port from shell scripts without hardcoding port numbers.
- Run a port server daemon on test infrastructure to coordinate port allocation across concurrent test processes.
- Avoid port conflicts when spinning up multiple service instances in integration tests.
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
Yes, for test automation and development.
The package is stable and has no known vulnerabilities, with low install friction. However, the repository is archived and unmaintained—if you encounter a bug or need a feature, you will need to fork or find an alternative. For production port coordination at scale, evaluate the included port server carefully or consider running it in a controlled test environment first.
Install
portpicker on PyPI
Before you install
Low friction install with a single runtime dependency (psutil). Maintenance is inactive—the repository is archived and the last release was 2023-08-15—but the package is marked as Production/Stable and has been in use since 2015.
Requires Python 3.6 or later. Race condition exists between port selection and binding; for production use, the documentation recommends running a port server daemon (included) and setting PORTSERVER_ADDRESS=@unittest-portserver.
License in practice
Licensed under Apache 2.0 (permissive), so you can use, modify, and distribute it freely in commercial and private projects without restriction.
Quickstart
import portpicker
test_port = portpicker.pick_unused_port()
# Or from command line:
# python3 -m portpicker $$Verify before relying
- Whether the port server daemon included in the package is production-ready or still considered experimental.
- Current state of the repository and whether critical bug fixes are still accepted despite archival status.
- Whether the race condition between picking a port and binding to it remains acceptable for modern test workloads.
Package facts
| License | Apache 2.0 permissive |
| Python support | Supports the current Python release >=3.6 |
| Install friction | Low. Pure-Python wheel |
| Runtime dependencies | 1 packagepsutil |
| Maintenance | Abandoned 1,095 days since the last release |
| Last repo commit | repository archived |
| First released | |
| Downloads | 3,396,179 / month, #2,636 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Development Status :: 5 - Production/StableIntended Audience :: DevelopersLicense :: OSI Approved :: Apache Software LicenseProgramming Language :: PythonProgramming Language :: Python :: 3Programming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.12Programming Language :: Python :: 3.7Programming Language :: Python :: 3.8Programming Language :: Python :: 3.9Programming Language :: Python :: Implementation :: CPythonProgramming Language :: Python :: Implementation :: PyPy |
Evidence: portpicker-1.6.0-py3-none-any.whl
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See also port-for · ephemeral-port-reserve · portend · uncalled · pick · pytest-socket · ping3 · cppclean · vulture · pytest-unused-fixtures