By Team Hypomnema · Updated October 19, 2026
Find text or regex matches and replace them with capture-group support.
Use and export
Paste text, load a UTF-8 file or try the sample.
Choose options and select Run. Review the result, counts and any warnings.
Copy or download the result in an available format. Run again after changing inputs.
Methods and limits
Patterns: 2,000 characters; replacement: 10,000; at most 20,000 matches. Regex runs in a worker with a five-second timeout. JavaScript Unicode regex syntax applies; $1, $<name>, $& and $$ replacements are supported. Prefix/suffix replacement tokens are not supported. Empty matches advance safely by code point.
Private processing
Text and files stay in browser memory and a local worker. No uploads, account access, network lookups or automatic storage. Refreshing clears your work. Input is limited to 500 KB and generated output to 1 MB; processing times out after five seconds. Downloads and clipboard copies contain the output you choose.
Try the workflow
Keep your original documents and review the output. You can also browse all guides or contact Team Hypomnema.