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Text Extractor via Regular Expressions

Extract matching text using regular expressions and capture groups, output to CSV.

100% Secure - your files are processed in your browser and never sent to a server.
Drop your file hereor click to browseSupports CSV, TSV, or TXT files (.csv, .tsv, .txt) (Max 100MB)

How to use the Regex Extractor tool

  1. Load your text: Drag and drop a text file, choose a file from your file explorer, or paste text directly into the paste area.
  2. Write a regex pattern: Enter a regular expression pattern to match (e.g. (\w+):\s*(\d+)). Use capture groups to extract specific parts.
  3. Configure flags: Toggle Ignore Case for case-insensitive matching and Multiline to make ^ and $ work across lines.
  4. Choose output format: Select CSV (capture groups become columns) or Plain List (matching strings only).
  5. Extract matches: Click the "Extract Matches" button to find all matching text, then copy or download the results.

Frequently asked questions

Is it safe to use Regex Extractor with sensitive or confidential data?
Yes, completely. All processing done by Regex Extractor runs 100% client-side inside your local web browser using a background Web Worker thread. Your data is never uploaded, transmitted, or stored on any server, not even temporarily.
What is the maximum file size Regex Extractor can handle?
Regex Extractor supports files up to 100 MB. Because all parsing happens inside your browser's memory rather than on a server, performance scales with your computer's available RAM. The Web Worker architecture keeps the UI fully responsive even during heavy processing.
How does Regex Extractor process my data without uploading it?
Regex Extractor uses modern browser File and Blob APIs alongside battle-tested open-source libraries (such as PapaParse and SheetJS) bundled directly into the page. When you load a file or paste data, the browser reads it into local memory and the conversion runs entirely inside a sandboxed Web Worker thread. No network call is ever made.
Do I need to install anything to use Regex Extractor?
No installation, browser extension, or plugin is required. Regex Extractor runs as a standard web page inside any modern browser. Simply open it, load your data, and download the output. Nothing to install and nothing to uninstall.
Does Regex Extractor work offline after the page has loaded?
Yes. Once Regex Extractor has finished loading in your browser, the conversion engine itself requires no active internet connection. You can disconnect from the network and continue converting files; all processing stays fully on-device.

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