Code & Dev Tools
Code & Dev Tools

Regex Tester

Test a regular expression against sample text with live highlighting, a match list, and named capture groups broken out per match. Flags are toggled with one click. Everything happens locally in your browser: nothing is uploaded, stored, or logged.

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Regex Tester · client-side FFmpeg

FileForge is bringing FFmpeg entirely inside your browser tab — nothing uploads. Enable this tool by turning on cross-origin isolation in your deployment (see ffmpegwasm.netlify.app), or use the desktop CLI in the meantime.

About Regex Tester

Test a regular expression against sample text with live highlighting, a match list, and named capture groups broken out per match. Flags are toggled with one click. Everything happens locally in your browser: nothing is uploaded, stored, or logged. This focused Regex Tester page is designed for developers and data workers building patterns for validation, extraction, search, and text cleanup. It opens directly to the working tool, rather than hiding the function inside a general converter or account dashboard.

The source is evaluated by a purpose-built parser or browser API in the current tab; it is not submitted to a remote formatter, compiler, or logging service. Your filename and file contents stay on the device. There is no upload queue, temporary cloud copy, account record, or server-side conversion job to delete later. That makes the tool practical for personal records, work material, and drafts that should not be handed to an unknown processing service.

The operation stays focused on live matching with highlighting. You can inspect the result immediately and repeat the task with different settings without a quota or watermark. Processing speed and maximum size depend on your browser and available device memory, which is the honest trade-off for doing the work locally.

FileForge charges nothing for this tool and does not add a watermark. Once the page and its processing engine have loaded, the operation can continue without sending the file over the network. Use the numbered steps below, download the result, and review it before replacing an original file.

How to use Regex Tester

  1. 1

    Open Regex Tester

    Stay on this dedicated Regex Tester page; no account, extension, or desktop installation is required.

  2. 2

    Add the input

    Paste the source text or choose a local file where the tool supports one.

  3. 3

    Set the options

    Choose the output, range, quality, or formatting controls shown for Regex Tester.

  4. 4

    Run the tool

    Start the operation and keep this tab open while your browser processes the input locally.

  5. 5

    Check and save

    Review the result, then copy it or download the new file to your device.

Regex Tester FAQ

What does Regex Tester do?
Test a regular expression against sample text with live highlighting, a match list, and named capture groups broken out per match. Flags are toggled with one click. Everything happens locally in your browser: nothing is uploaded, stored, or logged.
Who is Regex Tester useful for?
It is built for developers and data workers building patterns for validation, extraction, search, and text cleanup.
Is Regex Tester free?
Yes. Regex Tester is free to use, needs no account, and adds no FileForge watermark.
Does Regex Tester upload my file?
No. The input is processed in browser memory on your device and is not sent to FileForge or a conversion server.
What are the limits of Regex Tester?
There is no artificial daily quota. The practical limit is the memory and processing power available to your browser, so very large files work best on a desktop.
Can I use Regex Tester offline?
After this page and its processing library have loaded, the core operation can continue without uploading the input. Reloading the page may require a connection.
Which browsers support Regex Tester?
Current versions of Chrome, Edge, Firefox, and Safari are recommended. Media and unusually large files perform best on an up-to-date desktop browser.

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