glob is a file system walker that searches your disk for files matching a pattern. minimatch, micromatch, and picomatch are string matchers that test if a path or string fits a pattern without touching the disk. glob often uses one of the matchers internally to filter results. Choosing the right tool depends on whether you need to read the file system or just filter a list of paths in memory.
When working with file paths in Node.js, developers often confuse tools that walk the file system with tools that match strings. glob belongs to the first category, while minimatch, micromatch, and picomatch belong to the second. Understanding this distinction is critical for architectural decisions — using a string matcher to find files on disk will fail, and using a file walker to filter an in-memory array is wasteful.
glob actually reads your hard drive.
// glob: Searches the file system
import { glob } from 'glob';
const files = await glob('**/*.js', { cwd: './src' });
// Returns: ['src/index.js', 'src/utils/helper.js']
minimatch tests a single string against a pattern.
true or false.// minimatch: Tests a string
import { minimatch } from 'minimatch';
const isMatch = minimatch('src/index.js', '**/*.js');
// Returns: true
micromatch filters a list of strings against patterns.
// micromatch: Filters an array
import micromatch from 'micromatch';
const files = ['src/index.js', 'src/style.css', 'test/index.js'];
const matches = micromatch(files, '**/*.js');
// Returns: ['src/index.js', 'test/index.js']
picomatch compiles patterns into reusable matcher functions.
// picomatch: Compiles a matcher
import picomatch from 'picomatch';
const isJS = picomatch('**/*.js');
const result = isJS('src/index.js');
// Returns: true
All four packages support standard glob patterns, but their support for extensions like brace expansion varies.
glob supports standard globs and relies on its internal matcher for extensions.
*, **, ?, and character classes.// glob: With brace expansion option
import { glob } from 'glob';
const files = await glob('src/*.{js,ts}', { expand: true });
// Matches: src/index.js, src/app.ts
minimatch supports standard globs but has limited brace expansion.
braceExpansion option to be enabled.// minimatch: With brace expansion
import { minimatch } from 'minimatch';
const isMatch = minimatch('src/index.js', 'src/*.{js,ts}', { braceExpansion: true });
// Returns: true
micromatch has extensive support for glob extensions.
minimatch.// micromatch: Advanced patterns
import micromatch from 'micromatch';
const matches = micromatch(['a.js', 'b.ts'], '{a,b}.{js,ts}');
// Returns: ['a.js', 'b.ts']
picomatch supports the widest range of patterns with high accuracy.
// picomatch: Complex patterns
import picomatch from 'picomatch';
const isMatch = picomatch('**/*.{js,ts,tsx}');
const result = isMatch('components/Button.tsx');
// Returns: true
Performance matters when you are matching thousands of paths. glob is limited by disk speed, while the others are limited by CPU.
glob is I/O bound.
// glob: Async iteration for large sets
import { glob } from 'glob';
for await (const file of glob.iterate('**/*.log')) {
console.log(file); // Process as they are found
}
minimatch is slower on large arrays.
// minimatch: Looping manually
import { minimatch } from 'minimatch';
const files = getLargeFileList();
const matches = files.filter(f => minimatch(f, '**/*.js'));
micromatch is optimized for bulk filtering.
minimatch on large arrays.// micromatch: Bulk filter
import micromatch from 'micromatch';
// Fast filtering of 10,000 paths
const matches = micromatch(largePathArray, '!**/node_modules/**');
picomatch is the fastest for repeated tests.
// picomatch: Reused matcher function
import picomatch from 'picomatch';
const matcher = picomatch('**/*.spec.js');
// Run this function thousands of times with minimal overhead
const isSpec = matcher('tests/auth.spec.js');
These tools often work together. glob uses a matcher to filter files it finds. You can often swap the default matcher for better performance.
glob allows custom matchers.
picomatch or minimatch as the matcher option.// glob: Using custom matcher
import { glob } from 'glob';
import picomatch from 'picomatch';
const files = await glob('**/*.js', {
ignore: '**/vendor/**',
// Some versions allow specifying matcher implementation
});
micromatch is used by major tools.
picomatch in newer versions.// micromatch: Used in tool config
// webpack.config.js
module.exports = {
module: {
rules: [
{
test: micromatch.makeRe('**/*.js'),
exclude: micromatch.makeRe('**/node_modules/**')
}
]
}
};
minimatch is the legacy standard.
// minimatch: Legacy script
import { minimatch } from 'minimatch';
// Common in older CLI tools
if (minimatch(filePath, pattern)) {
processFile(filePath);
}
picomatch is the modern engine.
micromatch v4+.// picomatch: Building a custom tool
import picomatch from 'picomatch';
const scan = (files, pattern) => {
const isMatch = picomatch(pattern);
return files.filter(isMatch);
};
| Feature | glob | micromatch | minimatch | picomatch |
|---|---|---|---|---|
| Primary Role | 🗂️ File System Walker | 🧠 In-Memory Filter | 🧪 String Tester | ⚡ Matcher Engine |
| Returns | File Paths (Array/Async) | Filtered Paths (Array) | Boolean | Matcher Function |
| Disk Access | ✅ Yes | ❌ No | ❌ No | ❌ No |
| Speed | I/O Limited | Fast | Moderate | Fastest |
| Best For | Finding files on disk | Filtering path arrays | Simple validation | High-frequency checks |
glob is your go-to when you need to find files that actually exist on the disk. It handles the hard work of directory traversal and symlink resolution. Do not try to replicate this with string matchers.
micromatch is the best choice for filtering lists of paths in memory. If you are building a bundler, linter, or task runner that already has a list of files, use this to filter them quickly.
minimatch is suitable for simple scripts or legacy compatibility. It is reliable but slower than modern alternatives. Use it if you are maintaining older codebases or need a simple boolean check.
picomatch is the engine for maximum performance. Use it when you need to test the same pattern against thousands of strings repeatedly. It is also the best choice if you are building a library that needs glob matching capabilities.
Final Thought: Remember the golden rule — if you need to read the disk, use glob. If you already have the paths, use micromatch or picomatch. Mixing them up leads to slow code or broken features.
Choose minimatch for simple pattern matching needs where maximum performance is not critical. It is the historical standard used by many older tools and offers solid compatibility with bash globbing rules. Use it if you need to match single strings against a pattern reliably.
Choose picomatch when you need the fastest possible pattern matching engine. It is often used internally by other tools (like micromatch v4+) to compile patterns into reusable matcher functions. Select this for high-performance scenarios where you test the same pattern against many paths repeatedly.
Choose glob when you need to physically search the file system for files. It handles directory traversal, symlink resolution, and returns actual file paths. It is the standard choice for build scripts, test runners, and CLI tools that need to locate files on disk.
Choose micromatch when you have an existing list of file paths in memory and need to filter them quickly using complex glob patterns. It is ideal for bundlers, task runners, or any tool that processes large arrays of paths without needing to read the disk again.
A minimal matching utility.
This is the matching library used internally by npm.
It works by converting glob expressions into JavaScript RegExp
objects.
[!WARNING]
This library uses JavaScript regular expressions. Please read the following warning carefully, and be thoughtful about what you provide to this library in production systems.
Any library in JavaScript that deals with matching string patterns using regular expressions will be subject to ReDoS if the pattern is generated using untrusted input.
Efforts have been made to mitigate risk as much as is feasible in such a library, providing maximum recursion depths and so forth, but these measures can only ultimately protect against accidents, not malice. A dedicated attacker can always find patterns that cannot be defended against by a bash-compatible glob pattern matching system that uses JavaScript regular expressions.
To be extremely clear:
[!WARNING]
If you create a system where you take user input, and use that input as the source of a Regular Expression pattern, in this or any extant glob matcher in JavaScript, you will be pwned.
A future version of this library may use a different matching algorithm which does not exhibit backtracking problems. If and when that happens, it will likely be a sweeping change, and those improvements will not be backported to legacy versions.
In the near term, it is not reasonable to continue to play whack-a-mole with security advisories, and so any future ReDoS reports will be considered "working as intended", and resolved entirely by this warning.
// hybrid module, load with require() or import
import { minimatch } from 'minimatch'
// or:
const { minimatch } = require('minimatch')
minimatch('bar.foo', '*.foo') // true!
minimatch('bar.foo', '*.bar') // false!
minimatch('bar.foo', '*.+(bar|foo)', { debug: true }) // true, and noisy!
Supports these glob features:
** matching[[:alpha:]], supporting the full range of Unicode
characters. For example, [[:alpha:]] will match against
'é', though [a-zA-Z] will not. Collating symbol and set
matching is not supported, so [[=e=]] will not match 'é'
and [[.ch.]] will not match 'ch' in locales where ch is
considered a single character.See:
man shman bash Pattern
Matchingman 3 fnmatchman 5 gitignorePlease only use forward-slashes in glob expressions.
Though windows uses either / or \ as its path separator, only /
characters are used by this glob implementation. You must use
forward-slashes only in glob expressions. Back-slashes in patterns
will always be interpreted as escape characters, not path separators.
Note that \ or / will be interpreted as path separators in paths on
Windows, and will match against / in glob expressions.
So just always use / in patterns.
On Windows, UNC paths like //?/c:/... or
//ComputerName/Share/... are handled specially.
//* will match //x, but not /x.//?/<drive letter>: will not treat
the ? as a wildcard character. Instead, it will be treated
as a normal string.//?/<drive letter>:/... will match
file paths starting with <drive letter>:/..., and vice versa,
as if the //?/ was not present. This behavior only is
present when the drive letters are a case-insensitive match to
one another. The remaining portions of the path/pattern are
compared case sensitively, unless nocase:true is set.Note that specifying a UNC path using \ characters as path
separators is always allowed in the file path argument, but only
allowed in the pattern argument when windowsPathsNoEscape: true
is set in the options.
Create a minimatch object by instantiating the minimatch.Minimatch class.
var Minimatch = require('minimatch').Minimatch
var mm = new Minimatch(pattern, options)
pattern The original pattern the minimatch object represents.
options The options supplied to the constructor.
set A 2-dimensional array of regexp or string expressions.
Each row in the
array corresponds to a brace-expanded pattern. Each item in the row
corresponds to a single path-part. For example, the pattern
{a,b/c}/d would expand to a set of patterns like:
[ [ a, d ]
, [ b, c, d ] ]
If a portion of the pattern doesn't have any "magic" in it
(that is, it's something like "foo" rather than fo*o?), then it
will be left as a string rather than converted to a regular
expression.
regexp Created by the makeRe method. A single regular expression
expressing the entire pattern. This is useful in cases where you wish
to use the pattern somewhat like fnmatch(3) with FNM_PATH enabled.
negate True if the pattern is negated.
comment True if the pattern is a comment.
empty True if the pattern is "".
makeRe() Generate the regexp member if necessary, and return it.
Will return false if the pattern is invalid.
match(fname) Return true if the filename matches the pattern, or
false otherwise.
matchOne(fileArray, patternArray, partial) Take a /-split
filename, and match it against a single row in the regExpSet. This
method is mainly for internal use, but is exposed so that it can be
used by a glob-walker that needs to avoid excessive filesystem calls.
hasMagic() Returns true if the parsed pattern contains any
magic characters. Returns false if all comparator parts are
string literals. If the magicalBraces option is set on the
constructor, then it will consider brace expansions which are
not otherwise magical to be magic. If not set, then a pattern
like a{b,c}d will return false, because neither abd nor
acd contain any special glob characters.
This does not mean that the pattern string can be used as a
literal filename, as it may contain magic glob characters that
are escaped. For example, the pattern \\* or [*] would not
be considered to have magic, as the matching portion parses to
the literal string '*' and would match a path named '*',
not '\\*' or '[*]'. The minimatch.unescape() method may
be used to remove escape characters.
All other methods are internal, and will be called as necessary.
Main export. Tests a path against the pattern using the options.
var isJS = minimatch(file, '*.js', { matchBase: true })
Returns a function that tests its
supplied argument, suitable for use with Array.filter. Example:
var javascripts = fileList.filter(
minimatch.filter('*.js', { matchBase: true }),
)
Escape all magic characters in a glob pattern, so that it will only ever match literal strings.
If the windowsPathsNoEscape option is used, then characters are
escaped by wrapping in [], because a magic character wrapped in
a character class can only be satisfied by that exact character.
Slashes (and backslashes in windowsPathsNoEscape mode) cannot
be escaped or unescaped.
Un-escape a glob string that may contain some escaped characters.
If the windowsPathsNoEscape option is used, then square-brace
escapes are removed, but not backslash escapes. For example, it
will turn the string '[*]' into *, but it will not turn
'\\*' into '*', because \ is a path separator in
windowsPathsNoEscape mode.
When windowsPathsNoEscape is not set, then both brace escapes
and backslash escapes are removed.
Slashes (and backslashes in windowsPathsNoEscape mode) cannot
be escaped or unescaped.
Match against the list of files, in the style of fnmatch or glob. If nothing is matched, and options.nonull is set, then return a list containing the pattern itself.
var javascripts = minimatch.match(fileList, '*.js', { matchBase: true })
Make a regular expression object from the pattern.
All options are false by default.
Dump a ton of stuff to stderr.
Do not expand {a,b} and {1..3} brace sets.
Disable ** matching against multiple folder names.
Allow patterns to match filenames starting with a period, even if the pattern does not explicitly have a period in that spot.
Note that by default, a/**/b will not match a/.d/b, unless dot
is set.
Disable "extglob" style patterns like +(a|b).
Perform a case-insensitive match.
When used with {nocase: true}, create regular expressions that
are case-insensitive, but leave string match portions untouched.
Has no effect when used without {nocase: true}.
Useful when some other form of case-insensitive matching is used, or if the original string representation is useful in some other way.
When a match is not found by minimatch.match, return a list containing
the pattern itself if this option is set. When not set, an empty list
is returned if there are no matches.
This only affects the results of the Minimatch.hasMagic method.
If the pattern contains brace expansions, such as a{b,c}d, but
no other magic characters, then the Minimatch.hasMagic() method
will return false by default. When this option set, it will
return true for brace expansion as well as other magic glob
characters.
If set, then patterns without slashes will be matched
against the basename of the path if it contains slashes. For example,
a?b would match the path /xyz/123/acb, but not /xyz/acb/123.
Suppress the behavior of treating # at the start of a pattern as a
comment.
Suppress the behavior of treating a leading ! character as negation.
Returns from negate expressions the same as if they were not negated. (Ie, true on a hit, false on a miss.)
Compare a partial path to a pattern. As long as the parts of the path that are present are not contradicted by the pattern, it will be treated as a match. This is useful in applications where you're walking through a folder structure, and don't yet have the full path, but want to ensure that you do not walk down paths that can never be a match.
For example,
minimatch('/a/b', '/a/*/c/d', { partial: true }) // true, might be /a/b/c/d
minimatch('/a/b', '/**/d', { partial: true }) // true, might be /a/b/.../d
minimatch('/x/y/z', '/a/**/z', { partial: true }) // false, because x !== a
Use \\ as a path separator only, and never as an escape
character. If set, all \\ characters are replaced with / in
the pattern. Note that this makes it impossible to match
against paths containing literal glob pattern characters, but
allows matching with patterns constructed using path.join() and
path.resolve() on Windows platforms, mimicking the (buggy!)
behavior of earlier versions on Windows. Please use with
caution, and be mindful of the caveat about Windows
paths.
For legacy reasons, this is also set if
options.allowWindowsEscape is set to the exact value false.
When a pattern starts with a UNC path or drive letter, and in
nocase:true mode, do not convert the root portions of the
pattern into a case-insensitive regular expression, and instead
leave them as strings.
This is the default when the platform is win32 and
nocase:true is set.
By default, multiple / characters (other than the leading //
in a UNC path, see "UNC Paths" above) are treated as a single
/.
That is, a pattern like a///b will match the file path a/b.
Set preserveMultipleSlashes: true to suppress this behavior.
A number indicating the level of optimization that should be done to the pattern prior to parsing and using it for matches.
Globstar parts ** are always converted to * when noglobstar
is set, and multiple adjacent ** parts are converted into a
single ** (ie, a/**/**/b will be treated as a/**/b, as this
is equivalent in all cases).
0 - Make no further changes. In this mode, . and .. are
maintained in the pattern, meaning that they must also appear
in the same position in the test path string. Eg, a pattern
like a/*/../c will match the string a/b/../c but not the
string a/c.
1 - (default) Remove cases where a double-dot .. follows a
pattern portion that is not **, ., .., or empty ''. For
example, the pattern ./a/b/../* is converted to ./a/*, and
so it will match the path string ./a/c, but not the path
string ./a/b/../c. Dots and empty path portions in the
pattern are preserved.
2 (or higher) - Much more aggressive optimizations, suitable
for use with file-walking cases:
.. follows a pattern
portion that is not **, ., or empty ''. Remove empty
and . portions of the pattern, where safe to do so (ie,
anywhere other than the last position, the first position, or
the second position in a pattern starting with /, as this
may indicate a UNC path on Windows).<pre>/**/../<p>/<rest> into the
equivalent <pre>/{..,**}/<p>/<rest>, where <p> is a
a pattern portion other than ., .., **, or empty
''.** portion is present in one and
omitted in another, and it is not the final path portion, and
they are otherwise equivalent. So {a/**/b,a/b} becomes
a/**/b, because ** matches against an empty path portion.* portion is present in one, and a
non-dot pattern other than **, ., .., or '' is in the
same position in the other. So a/{*,x}/b becomes a/*/b,
because * can match against x.While these optimizations improve the performance of file-walking use cases such as glob (ie, the reason this module exists), there are cases where it will fail to match a literal string that would have been matched in optimization level 1 or 0.
Specifically, while the Minimatch.match() method will
optimize the file path string in the same ways, resulting in
the same matches, it will fail when tested with the regular
expression provided by Minimatch.makeRe(), unless the path
string is first processed with
minimatch.levelTwoFileOptimize() or similar.
When set to win32, this will trigger all windows-specific
behaviors (special handling for UNC paths, and treating \ as
separators in file paths for comparison.)
Defaults to the value of process.platform.
Max number of non-adjacent ** patterns to recursively walk
down.
The default of 200 is almost certainly high enough for most
purposes, and can handle absurdly excessive patterns.
If the limit is exceeded (which would require very excessively
long patterns and paths containing lots of ** patterns!), then
it is treated as non-matching, even if the path would normally
match the pattern provided.
That is, this is an intentional false negative, deemed an acceptable break in correctness for security and performance.
Max depth to traverse for nested extglobs like *(a|b|c)
Default is 2, which is quite low, but any higher value swiftly results in punishing performance impacts. Note that this is not relevant when the globstar types can be safely coalesced into a single set.
For example, *(a|@(b|c)|d) would be flattened into
*(a|b|c|d). Thus, many common extglobs will retain good
performance and never hit this limit, even if they are
excessively deep and complicated.
If the limit is hit, then the extglob characters are simply not
parsed, and the pattern effectively switches into noextglob: true mode for the contents of that nested sub-pattern. This will
typically not result in a match, but is considered a valid
trade-off for security and performance.
While strict compliance with the existing standards is a worthwhile goal, some discrepancies exist between minimatch and other implementations. Some are intentional, and some are unavoidable.
If the pattern starts with a ! character, then it is negated. Set the
nonegate flag to suppress this behavior, and treat leading !
characters normally. This is perhaps relevant if you wish to start the
pattern with a negative extglob pattern like !(a|B). Multiple !
characters at the start of a pattern will negate the pattern multiple
times.
If a pattern starts with #, then it is treated as a comment, and
will not match anything. Use \# to match a literal # at the
start of a line, or set the nocomment flag to suppress this behavior.
The double-star character ** is supported by default, unless the
noglobstar flag is set. This is supported in the manner of bsdglob
and bash 4.1, where ** only has special significance if it is the only
thing in a path part. That is, a/**/b will match a/x/y/b, but
a/**b will not.
If an escaped pattern has no matches, and the nonull flag is set,
then minimatch.match returns the pattern as-provided, rather than
interpreting the character escapes. For example,
minimatch.match([], "\\*a\\?") will return "\\*a\\?" rather than
"*a?". This is akin to setting the nullglob option in bash, except
that it does not resolve escaped pattern characters.
If brace expansion is not disabled, then it is performed before any
other interpretation of the glob pattern. Thus, a pattern like
+(a|{b),c)}, which would not be valid in bash or zsh, is expanded
first into the set of +(a|b) and +(a|c), and those patterns are
checked for validity. Since those two are valid, matching proceeds.
Negated extglob patterns are handled as closely as possible to
Bash semantics, but there are some cases with negative extglobs
which are exceedingly difficult to express in a JavaScript
regular expression. In particular the negated pattern
<start>!(<pattern>*|)* will in bash match anything that does
not start with <start><pattern>. However,
<start>!(<pattern>*)* will match paths starting with
<start><pattern>, because the empty string can match against
the negated portion. In this library, <start>!(<pattern>*|)*
will not match any pattern starting with <start>, due to a
difference in precisely which patterns are considered "greedy" in
Regular Expressions vs bash path expansion. This may be fixable,
but not without incurring some complexity and performance costs,
and the trade-off seems to not be worth pursuing.
Note that fnmatch(3) in libc is an extremely naive string comparison
matcher, which does not do anything special for slashes. This library is
designed to be used in glob searching and file walkers, and so it does do
special things with /. Thus, foo* will not match foo/bar in this
library, even though it would in fnmatch(3).