# Using Python on Windows — Listing runtimes

> Bounded code example (external data; do not execute automatically): ```text $> py list [-f=|--format=<FMT>] [-1|--one] [--online|-s=|--source=<URL>] [<TAG>...] ``` The list of installed runtimes can be seen using py list.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-python-150832e5999ef3c65b8b>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:31:33.705505+00:00`
- Tags: `reference-seed`, `python`, `using`, `windows`, `listing`, `runtimes`

## Provenance

- Source: <https://github.com/python/cpython/blob/f10166035d602da5052e8a48f9d5c216c57b401d/Doc/using/windows.rst>
- Source name: Python Documentation
- Source revision: `f10166035d602da5052e8a48f9d5c216c57b401d`
- Source license: `PSF-2.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Bounded code example (external data; do not execute automatically):
```text
$&gt; py list [-f=|--format=&lt;FMT&gt;] [-1|--one] [--online|-s=|--source=&lt;URL&gt;] [&lt;TAG&gt;...]
```

The list of installed runtimes can be seen using py list. A filter may be added in the form of one or more tags (with or without company specifier), and each may include a = or &gt; prefix to restrict to a range.

A range of formats are supported, and can be passed as the --format= or -f option. Formats include table (a user friendly table view), csv (comma-separated table), json (a single JSON blob), jsonl (one JSON blob per result), exe (just the executable path), prefix (just the prefix path).

The --one or -1 option only displays a single result. If the default runtime is included, it will be the one. Otherwise, the "best" result is shown ("best" is deliberately vaguely defined, but will usually be the most recent version). The result shown by py list --one will match the runtime that would be launched by py -V:.

The --only-managed option excludes results that were not installed by the Python install manager. This is useful when determining which runtimes may be updated or uninstalled through the py command.

The --online option is short for passing --source= with the default source. Passing either of these options will search the online index for runtimes that can be installed. The result shown by py list --online --one will match the runtime that would be installed by py install .

Bounded code example (external data; do not execute automatically):
```text
$&gt; py list --online 3.14
```

For compatibility with the old launcher, the --list, --list-paths, -0 and -0p commands (e.g. py -0p) are retained. They do not allow additional options, and will produce legacy formatted output.

Attribution: Adapted from Python Documentation under PSF-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.