HTML Entity Encoder/Decoder
Encode special characters like &, <, >, and quotes into HTML entities, or decode HTML entities back to their original characters.
How Does the HTML Entity Encoder/Decoder Work?
The HTML Entity Encoder/Decoder is a free online tool designed for web developers, content creators, and anyone who works with HTML markup. HTML entities are special character sequences that represent characters which have reserved meaning in HTML or cannot be easily typed on a standard keyboard. For example, the less-than sign (<) and greater-than sign (>) are used to define HTML tags, so if you want to display these characters as visible text on a web page, you must use their entity equivalents: < and >.
When you encode text, this tool replaces the five most critical HTML special characters with their corresponding entity references. The ampersand (&) becomes &, the less-than sign (<) becomes <, the greater-than sign (>) becomes >, double quotes (") become ", and single quotes (') become '. These replacements prevent the browser from interpreting your text as HTML markup, which is essential for displaying code snippets on web pages and preventing cross-site scripting (XSS) attacks.
When you decode text, the tool performs the reverse operation. It takes HTML entity references and converts them back to their original characters. This is useful when you need to extract plain text from HTML source code, convert entity-encoded content for use in non-HTML contexts, or simply read text that has been encoded for safe HTML display. The decoder uses the browser's built-in HTML parser by creating a temporary DOM element, which ensures accurate and comprehensive decoding of both named entities (like &) and numeric entities (like &).
Why HTML Entity Encoding Matters
HTML entity encoding is a critical security practice in web development. One of the most common web vulnerabilities is Cross-Site Scripting (XSS), where an attacker injects malicious HTML or JavaScript into a web page by submitting unencoded content through forms, URL parameters, or other user inputs. When a web application displays user-generated content without properly encoding HTML special characters, the browser may interpret injected script tags as executable code, compromising the security of every user who views the page.
By encoding all user-supplied content before inserting it into HTML output, developers can neutralize XSS attacks. An injected script tag like <script>alert('hack')</script> becomes harmless text that the browser displays literally rather than executes. Every major web framework includes built-in HTML encoding functions, and understanding how this encoding works is fundamental knowledge for secure web development.
Common HTML Entities
&— ampersand (&)<— less-than sign (<)>— greater-than sign (>)"— double quotation mark (")'or'— single quotation mark (') — non-breaking space©— copyright symbol—— em dash
When to Use This Tool
Web developers frequently need to encode text when embedding user content, code samples, or special characters in HTML pages. Content management systems, email templates, and RSS feeds all require proper entity encoding to display correctly. Conversely, when you copy HTML source code and need to read the actual text content, decoding entities makes the text human-readable again. This tool provides instant encoding and decoding without requiring any programming knowledge or access to a command-line environment.