Regex Escape — Escape Special Characters for a Literal Match

Real-world use cases

• Build a literal search out of user input

  You let users type a search term and you feed it into a RegExp to highlight matches. If someone searches for "C++" or "a.b", the raw regex blows up or matches the wrong thing — the plus is a quantifier, the dot is a wildcard. Escape the input first and the search matches exactly what they typed. This is the canonical use of re.escape / RegExp.escape, and the tool lets you see the escaped form before you wire it in.

• Match a version number or domain literally

  Filtering logs for "1.0.3" or "api.stripe.com"? Unescaped, those dots are wildcards, so 1.0.3 also matches 10503 and api.stripe.com matches apiXstripeYcom. Paste the string here, copy the escaped /1\.0\.3/, and your grep or log query stops catching false positives that the dots quietly let through.

• Hand-tune a generated pattern, then reverse it

  You inherited a regex like a\.b\*c and want to know what literal it was built from. Drop it into unescape mode and read back a.b*c. Tweak the plain text, flip to escape, and you have a clean rebuilt pattern — no counting backslashes by hand and no guessing which ones were real regex tokens versus escaped literals.

• Teach or document how escaping works

  Writing a tutorial or answering a Stack Overflow question about why a.b matches too much? Share a link with the input pre-filled — the URL carries the literal and options — and the reader lands on the exact before/after, including the ready /a\.b/ form. It is a faster explanation than a paragraph, and they can edit it live.

Common pitfalls

• Escaping the result a second time. If your language already has re.escape or RegExp.escape, do not also paste the output here — double escaping turns a\.b into a\\.b, which now matches a backslash followed by any char. Escape once, at the point where literal text enters the pattern.

• Forgetting that the backslash itself needs escaping. A literal backslash in your text must become \\ in the pattern, or it pairs with the next character and changes its meaning. The tool handles this, but hand-written escapers often miss it and produce patterns that silently match the wrong thing.

• Escaping the forward slash when you do not need to. The slash is only special as a JavaScript /literal/ delimiter. If you build the regex from a string, escaping the slash adds a stray backslash that some engines reject or treat as literal. Leave the slash option off unless you are writing the pattern between /…/ delimiters.

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