PureTools

Regex Cheatsheet

Quick reference of regular expressions with examples.

Start of string
End of string
Word boundary
Non-word boundary
0 or more
1 or more
0 or 1 (optional)
Exactly n times
n or more times
Between n and m times
0 or more (lazy)
1 or more (lazy)
Any character except newline
Digit [0-9]
Non-digit
Word character [a-zA-Z0-9_]
Non-word character
Whitespace
Non-whitespace
Character set (a, b, or c)
Negated set (not a, b, or c)
Range (a to z)
Capturing group
Non-capturing group
Named capturing group
Alternation (a or b)
Backreference to group 1
Positive lookahead
Negative lookahead
Positive lookbehind
Negative lookbehind
Email address
URL
CPF (Brazilian)
CNPJ (Brazilian)
Hex color
Date (YYYY-MM-DD)
Strong password (8+ chars, upper, lower, digit)

What is it?

Regex Cheatsheet is a free online tool that runs entirely in your browser. Quick reference of regular expressions with examples. No data is sent to any server — all processing happens locally on your device, ensuring complete privacy and security. Whether you're a developer, designer, student, or professional, this tool saves you time by providing instant results without requiring any software installation or account creation.

How to use

Using Regex Cheatsheet is straightforward. Simply enter or paste your data in the input field, configure any available options, and click the action button to process. The result appears instantly in the output area. You can copy the result to your clipboard with one click. If you need to start over, just clear the input and try again. The tool accepts a wide range of inputs and handles edge cases gracefully.

When to use

Regex Cheatsheet is useful in many everyday scenarios. Developers use it during coding sessions to quickly process data without leaving the browser. It's also perfect for one-off tasks where installing a dedicated application would be overkill. Students and learners find it helpful for understanding how the underlying process works. Since it's web-based, you can use it from any device — desktop, laptop, tablet, or phone — without any setup.

Frequently Asked Questions

Is Regex Cheatsheet free to use?▾
Yes, Regex Cheatsheet is completely free with no usage limits, no account required, and no ads that block functionality. All features are available immediately.
Is my data safe when using Regex Cheatsheet?▾
Absolutely. All processing happens directly in your browser using JavaScript. Your data never leaves your device and is never sent to any external server. You can verify this by checking your browser's network tab.
Does Regex Cheatsheet work on mobile devices?▾
Yes, the tool is fully responsive and works on all modern browsers including Chrome, Firefox, Safari, and Edge on any device — desktop, tablet, or smartphone.
Do I need to install anything to use Regex Cheatsheet?▾
No installation is needed. Regex Cheatsheet runs entirely in your web browser. Just open the page and start using it immediately. There's no signup, no download, and no browser extension required.

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