List the matches of an expression

Developers can use this while debugging or preparing data for an exchange, especially when the result needs a quick visual check. List the matches of an expression.

List the matches of an expression. The result appears instantly in your browser, ready to copy, with no account, upload or storage involved.

How to use

Enter the regular expression pattern in the first field provided for it.
Set the flags you need, for example gi, depending on what you want to check.
Paste the text to inspect into the text area, or import an accepted text, CSV, JSON, Markdown, XML or YAML file.
Run the test to display the list of matches found.
Review the results, adjust the pattern or flags if needed, then erase everything after checking.

Example

A developer needs to confirm that an expression finds contact addresses in a configuration excerpt. They enter a simple pattern with gi flags, paste text containing several addresses and review the listed matches before putting the pattern into their program.

Input

\b\w+@\w+\.com\b
gi
contact@example.com and support@example.org

Output

1. contact@example.com (index 0)

Limits and formats

The test follows the regular expression engine available in the browser, not the engine of every language.
The tool lists matches; it does not replace text or generate replacement code.
A very broad pattern can produce many matches and make the result hard to read.
Check capturing groups and accented characters with your real data, because behaviour can vary.
Flags must be supported by the engine being used; an unknown flag can make the test fail.

Where processing happens

The test runs entirely inside your browser. The pattern, flags and analysed text are not uploaded outside. Close the page or clear the fields to remove the content from the screen.

Frequently asked questions

What do flags such as gi mean?

The g flag asks for all matches instead of stopping at the first one. The i flag ignores uppercase and lowercase differences. Other flags may exist depending on the engine, but their support depends on the environment being used.

Why does my expression work here but not in my language?

Regular expression engines do not all behave the same way. A syntax accepted in the browser may not exist elsewhere, and the opposite can also happen. Test the pattern in the final environment before deploying it.

Can I test a very large file?

You can import an accepted text, CSV, JSON, Markdown, XML or YAML file, but a very long content can make the results hard to read. For large volumes, extract a representative sample before running the test.