Find & Replace

Search any block of text and rewrite it — in plain text or as a regular expression. The match counter and inline highlights update as you type. With preserve case turned on, the replacement adapts to each match’s case shape, so renaming foo to bar turns MyFooWidget into MyBarWidget, fooWidget into barWidget, and FOO into BAR. Nothing leaves your browser.

Input —

Find & replace —

Find

Replace with

Regex — treat the find field as a regular expression Case sensitive — Foo and foo are different Whole word — only match when surrounded by non-word characters Multiline — ^ and $ match line boundaries (regex only) Preserve case — adapt the replacement to each match’s case shape

Result —

Backreferences in the replacement

When the find field is a regex, the replacement supports the same backreferences as JavaScript’s String.prototype.replace:

$& — the entire match
$1, $2, ... — the 1st, 2nd, ... capture group
$\` — the text before the match
$' — the text after the match
$$ — a literal $

Preserve case

The tool detects the case shape of each match and rewrites the replacement to match. The five shapes it understands:

UPPERCASE — FOO → BAR
lowercase — foo → bar
Title Case — Foo → Bar
PascalCase — FooBar → BarBaz (when the replacement is bar baz)
camelCase — fooBar → barBaz

Tip for renaming identifiers: turn on regex and use a pattern like \bfoo\w+ to match the full identifier (foo, fooBar, FOO_BAR).