Find and replace text

Substitute literal text or an ECMAScript regular-expression pattern once or globally, with explicit case and word-boundary controls.

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ToolFind & Replace
Input
Output
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How it works

Literal mode escapes regex metacharacters before optional \b wrapping; regex mode compiles the entered source directly. Flags g and i control global matching and case folding, then String.prototype.replace interprets ECMAScript replacement tokens such as $&, $1, and $$.

  • Literal, case-sensitive, replace-all behavior is selected first because it gives ordinary text search predictable semantics.
  • Invalid raw patterns fail during RegExp construction before any source text is changed.

Worked example

Simple text replacement
Replace all occurrences of a word in text
Input
											Input: The quick brown fox jumps over the lazy fox.
Find: fox
Replace: cat
Output
												The quick brown cat jumps over the lazy cat.

When to use this

Documentation edits rename terms, log cleanup removes timestamp patterns, and delimited-data repairs replace exact separators.

Edge cases

  • An unclosed parenthesis in regex mode raises a pattern error instead of performing a partial substitution.
  • Whole-word mode uses JavaScript \b, so accented and non-Latin letters do not participate as full Unicode word characters.
  • Replacement $& inserts the complete match, $1 inserts a captured group, and $$ inserts one literal dollar sign.

References