JavaScript Regex Cheatsheet - Online Interactive Pattern Reference
Interactive cheatsheet for JavaScript regular expressions with live examples. Click any token to see its explanation and test it on sample text immediately.
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Quickly find, search & copy HTML symbol entities for your projects
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< displays the less-than symbol < without the browser mistaking it for an HTML tag. Using entities ensures your content renders correctly across all browsers, avoids encoding issues, and is essential for displaying reserved characters like &, <, >, and " in your HTML documents.
&) are easy to remember and read, but not every Unicode character has a named entity. Numeric codes come in two forms: decimal (&) and hexadecimal (&). Numeric codes can represent any Unicode character, making them more universal. Named entities are generally preferred for readability, while numeric codes are used when a name doesn't exist or when working with dynamic content.
<, >, &, ") to prevent parsing errors. Entities are also useful when your keyboard lacks certain symbols, when working in CMS platforms that may strip special characters, or when you need guaranteed cross-platform consistency in email HTML or legacy systems.
content: "\00A9"; for the copyright symbol ©. In JavaScript, use Unicode escape sequences like "\u00A9" or template literals with direct Unicode characters. When injecting HTML via JavaScript's innerHTML, you can use entity names like ©, but when using textContent, use the actual character or Unicode escape. For React/JSX, you can use entities directly in JSX markup or use JavaScript Unicode escapes in expressions.
(or  ) creates a space character that prevents an automatic line break at that position. Use it to keep related words together (e.g., "10 km"), in table cells that shouldn't collapse, or to create indentation. However, avoid using multiple for layout spacing — use CSS margins and padding instead. Overusing can create accessibility issues for screen readers and make responsive design harder to manage.
| Symbol | Entity Name | Decimal | Hex | Description |
|---|---|---|---|---|
| & | & | & | & | Ampersand |
| < | < | < | < | Less than |
| > | > | > | > | Greater than |
| " | " | " | " | Double quote |
| ' | ' | ' | ' | Single quote |
| © | © | © | © | Copyright |
| ® | ® | ® | ® | Registered trademark |
| € | € | € | € | Euro currency |
| — | — | — | — | Em dash |
|   |   | Non-breaking space |
Interactive cheatsheet for JavaScript regular expressions with live examples. Click any token to see its explanation and test it on sample text immediately.
An interactive reference for regular expression tokens. Click a token to see its explanation and example. Learn regex faster.
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