How to use Regular Expressions (Regex)?

Toggle the "Regular Expression" switch. You can now use standard JavaScript RegEx patterns. For example, use \d+ to match matching numbers, ^Start to match the start of a line, or \w+ to match words.

Can I use capturing groups?

Yes! You can use parentheses () to create capturing groups in the Find field, and reference them in the Replace field using $1, $2, etc. For example, Find: (\w+)-(\d+) and Replace: $2-$1 will swap the word and number.

Common Regex Examples

• Remove all numbers: \d+ • Find emails: [\w.-]+@[\w.-]+\.[a-z]{2,} • Match start of line: ^ • Match end of line: $

Is it case sensitive?

By default no, but you can enable "Match Case" for strict case sensitivity.

Absolutely. All processing happens in your browser. Nothing is ever sent to a server.

Find & Replace

Free online bulk find and replace tool. Search and replace text patterns instantly. Supports regular expressions (Regex), case sensitivity, and whole word matching. Perfect for code refactoring and content editing.

100% Private (In-Browser)Instant Web Worker SpeedZero Server Upload

Find & Replace by Privacy-First Toolbox is a 100% free, client-side browser utility. It processes your files locally on your computer or smartphone using HTML5 and Web Workers—zero bytes of your files or data are ever uploaded to any external server.

Find

Replace with

Match Case

Regular Expression

Whole Word Only

Source Text

Result

Key Features

Regular Expression (Regex) support
Case sensitive matching
Whole word matching
Real-time match counting
Instant result preview
One-click copy result

Common Use Cases

Refactor code variables
Update content templates
Clean up data formatting
Complex regex substitutions

Frequently Asked Questions

🔒100% Client-Side: Your text never leaves your device.

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