Match Patterns

Introduction

Content scripts operate on a set of URLs defined by match patterns. You can put one or more match patterns in the matches part of a content script’s section of the manifest, as well as in the exclude_matches section. This page describes the match pattern syntax — the rules you need to follow when you specify which URLs your content script affects.

What match patterns are

A match pattern is essentially a URL that begins with a permitted scheme (http, https, file, ftp, or chrome-extension), and that can contain * characters. The special pattern <all_urls> matches any URL that starts with a permitted scheme. Each match pattern has 3 parts:

scheme — for example, http or file or *
host — for example, www.google.com or *.google.com or *; if the scheme is file, there is no host part
path — for example, /*, /foo*, or /foo/bar

Note: Access to file URLs isn’t automatic. The user must visit the extensions management page and opt in to file access for each extension that requests it.

Match pattern syntax

Here’s the basic syntax:

<url-pattern> := <scheme>://<host><path>
<scheme> := `*` | `http` | `https` | `file` | `ftp` | `chrome-extension`
<host> := `*` | `*.` <any char except `/` and `*`>+
<path> := `/` <any chars>

The meaning of * depends on whether it’s in the scheme, host, or path part. If the scheme is *, then it matches either http or https. If the host is just *, then it matches any host. If the host is *.hostname, then it matches the specified host or any of its subdomains. In the path section, each * matches 0 or more characters. The following table shows some valid patterns.

Pattern	What it does	Examples of matching URLs
`http:///`	Matches any URL that uses the `http` scheme	`http://www.google.com/`, `http://example.org/foo/bar.html`
`http:///foo`	Matches any URL that uses the `http` scheme, on any host, as long as the path starts with `/foo`	`http://example.com/foo/bar.html`, `http://www.google.com/foobar`
`https://.google.com/foobar`	Matches any URL that uses the `https` scheme, is on a `google.com` host (such as `www.google.com`, `docs.google.com`, or `google.com`), as long as the path starts with `/foo` and ends with `bar`	`http://www.google.com/foo/baz/bar`, `http://docs.google.com/foobar`
`http://example.org/foo/bar.html`	Matches the specified URL	`http://example.org/foo/bar.html`
`file:///foo*`	Matches any local file whose path starts with `/foo`	`file:///foo/bar.html`, `file:///foo`
`http://127.0.0.1/*`	Matches any URL that uses the `http` scheme and is on the host `127.0.0.1`	`http://127.0.0.1/`, `http://127.0.0.1/foo/bar.html`
`://mail.google.com/`	Matches any URL that starts with `http://mail.google.com` or `https://mail.google.com`	`http://mail.google.com/foo/baz/bar`, `https://mail.google.com/foobar`
`chrome-extension:///`	Matches any URL pointing to an extension (the first `*` represents a filter for extension IDs, the second for paths)	`chrome-extension://askla…asdf/options.html`
`<all_urls>`	Matches any URL that uses a permitted scheme. (See the beginning of this section for the list of permitted schemes.)	`http://example.org/foo/bar.html`, `file:///bar/baz.html`

Here are some examples of invalid pattern matches:

Bad pattern	Why it’s bad
`http://www.google.com`	No `path`
`http://*foo/bar`	`*` in the `host` can be followed only by a `.` or `/`
`http://foo.*.bar/baz`	If `*` is in the `host`, it must be the first character
`http:/bar`	Missing `scheme` separator (`/` should be `//`)
`foo://*`	Invalid `scheme`

Some schemes are not supported in all contexts.