Home / Text / Safe Regex Tester and Text Replace

Safe Regex Tester and Text Replace

Test patterns and replacements without freezing the site.

This calculator runs in your browser. Nothing is sent to a server.

Pattern

JavaScript regular expression syntax (not PCRE).

Text

Flags

Operation

Replacement

JavaScript replacement: $1, $&, $$, $`, $'.

Timeout ms

Max characters

Engine

How it works

Processing stays in this browser tab. Source files are not uploaded. Export is a new copy; originals are not overwritten.