npxRun a command from a local or remote npm package
npx -- <pkg>[@<version>] [args...]npx --package=<pkg>[@<version>] -- <cmd> [args...]npx -c '<cmd> [args...]'npx --package=foo -c '<cmd> [args...]'
This command allows you to run an arbitrary command from an npm package
(either one installed locally, or fetched remotely), in a similar context
as running it via
Whatever packages are specified by the
--package option will be
provided in the
PATH of the executed command, along with any locally
installed package executables. The
--package option may be
specified multiple times, to execute the supplied command in an environment
where all specified packages are available.
If any requested packages are not present in the local project
dependencies, then they are installed to a folder in the npm cache, which
is added to the
PATH environment variable in the executed process. A
prompt is printed (which can be suppressed by providing either
Package names provided without a specifier will be matched with whatever version exists in the local project. Package names with a specifier will only be considered a match if they have the exact same name and version as the local dependency.
--call option is provided, then the positional arguments
are used to generate the command string. If no
are provided, then npm will attempt to determine the executable name from
the package specifier provided as the first positional argument according
to the following heuristic:
- If the package has a single entry in its
package.json, or if all entries are aliases of the same command, then that command will be used.
- If the package has multiple
binentries, and one of them matches the unscoped portion of the
namefield, then that command will be used.
- If this does not result in exactly one option (either because there are
no bin entries, or none of them match the
nameof the package), then
npm execexits with an error.
To run a binary other than the named binary, specify one or more
--package options, which will prevent npm from inferring the package from
the first command argument.
When run via the
npx binary, all flags and options must be set prior to
any positional arguments. When run via
npm exec, a double-hyphen
flag can be used to suppress npm's parsing of switches and options that
should be sent to the executed command.
$ npx foo@latest bar --package=@npmcli/foo
In this case, npm will resolve the
foo package name, and run the
$ foo bar --package=@npmcli/foo
--package option comes after the positional arguments, it is
treated as an argument to the executed command.
In contrast, due to npm's argument parsing logic, running this command is different:
$ npm exec foo@latest bar --package=@npmcli/foo
In this case, npm will parse the
--package option first, resolving the
@npmcli/foo package. Then, it will execute the following command in that
$ foo@latest bar
The double-hyphen character is recommended to explicitly tell npm to stop
parsing command line options and switches. The following command would
thus be equivalent to the
npx command above:
$ npm exec -- foo@latest bar --package=@npmcli/foo
Run the version of
tap in the local dependencies, with the provided
$ npm exec -- tap --bail test/foo.js$ npx tap --bail test/foo.js
Run a command other than the command whose name matches the package name
by specifying a
$ npm exec --package=foo -- bar --bar-argument# ~ or ~$ npx --package=foo bar --bar-argument
Run an arbitrary shell script, in the context of the current project:
$ npm x -c 'eslint && say "hooray, lint passed"'$ npx -c 'eslint && say "hooray, lint passed"'
Compatibility with Older npx Versions
npx binary was rewritten in npm v7.0.0, and the standalone
package deprecated at that time.
npx uses the
command instead of a separate argument parser and install process, with
some affordances to maintain backwards compatibility with the arguments it
accepted in previous versions.
This resulted in some shifts in its functionality:
npmconfig value may be provided.
- To prevent security and user-experience problems from mistyping package
npxprompts before installing anything. Suppress this prompt with the
--no-installoption is deprecated, and will be converted to
- Shell fallback functionality is removed, as it is not advisable.
-pargument is a shorthand for
--parseablein npm, but shorthand for
--packagein npx. This is maintained, but only for the
--ignore-existingoption is removed. Locally installed bins are always present in the executed process
--npmoption is removed.
npxwill always use the
npmit ships with.
-noptions are removed.
--always-spawnoption is redundant, and thus removed.
--shelloption is replaced with
--script-shell, but maintained in the
npxexecutable for backwards compatibility.