Regex Escape Tool

About this calculator

Regular expressions treat certain characters as metacharacters with special meaning — a period matches any character, an asterisk means zero or more, parentheses group patterns, and so on. If you want to search for those characters literally (a period in a filename, a dollar sign in a price), you have to escape each one with a backslash so the regex engine treats it as plain text instead of an instruction.

This tool automatically prefixes every metacharacter in your input — including the period, asterisk, plus, question mark, parentheses, brackets, braces, pipe, caret, dollar sign, and backslash itself — with a backslash, producing a string safe to drop into any regex pattern. It's equivalent to what functions like JavaScript's RegExp.escape, Python's re.escape, or PHP's preg_quote do programmatically.

Developers reach for this when building a regex dynamically from user input — like a search box — where an unescaped special character would either throw a syntax error or silently match the wrong things.