Extract with Regex from CSV Files Online
Extract text matching a regular expression from CSV files directly in your browser. Pull out emails, URLs, phone numbers, or any pattern into a new column — no upload required.
About this tool
Pull specific patterns out of text columns in a CSV file using regular expressions. Extract emails, phone numbers, URLs, product codes, or any repeating pattern into a new column — ready to download. All processing runs locally in your browser.
Frequently Asked Questions
What regex syntax does the CSV regex extract tool use?
This tool uses RE2 regular expression syntax. All common patterns work — character classes, quantifiers, alternation, and capture groups. Lookaheads and backreferences are not supported.
Can I extract multiple matches from one column in a CSV file?
Yes. Choose "All matches" mode to extract every occurrence of the pattern from each cell, returned as a comma-separated list.
What happens if a row does not match the pattern in a CSV file?
The extracted column will be null for that row. All other columns are preserved unchanged.
Is my data private?
Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.
What is the maximum file size?
The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.
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