Codificador/Decodificador Entidades HTML

Convierte caracteres especiales a entidades HTML y viceversa. Esencial para mostrar caracteres especiales correctamente en HTML y prevenir vulnerabilidades XSS.

What are HTML Entities?

HTML entities are special codes used to display reserved and special characters in HTML documents. An HTML entity begins with an ampersand (&) and ends with a semicolon (;), with either a descriptive name or numeric code in between. These entities are essential for web developers because they allow you to display characters that would otherwise be interpreted as HTML code by the browser. Using HTML entities correctly not only ensures proper character display but also plays a crucial role in preventing Cross-Site Scripting (XSS) security vulnerabilities on your website.

How to Use This Free HTML Entities Encoder

Our HTML entities encoder tool is designed for maximum simplicity. To encode text to HTML entities, paste your content into the input field and click "Encode to HTML Entities" to convert special HTML characters, or click "Encode All Characters" to convert every character to numeric entities. To decode HTML entities back to regular text, paste the entity-encoded text and click "Decode HTML Entities". All encoding and decoding happens instantly in your browser, ensuring your data remains private and secure. This tool is perfect for web developers, email template designers, content managers, and anyone working with HTML code.

Common HTML Entities Reference

Here are the most frequently used HTML entities every web developer should know:

  • < (less than sign) → &lt; or &#60;
  • > (greater than sign) → &gt; or &#62;
  • & (ampersand) → &amp; or &#38;
  • " (quotation mark) → &quot; or &#34;
  • ' (apostrophe) → &apos; or &#39;
  •   (non-breaking space) → &nbsp; or &#160;
  • © (copyright symbol) → &copy; or &#169;
  • ® (registered trademark) → &reg; or &#174;
  • ™ (trademark) → &trade; or &#8482;
  • € (Euro sign) → &euro; or &#8364;

Understanding the Two Encoding Methods

Our HTML entity encoder offers two powerful encoding options:

  • Encode HTML Entities: This method converts only the five special HTML characters that have specific meaning in HTML: less than (<), greater than (>), ampersand (&), quotation mark ("), and apostrophe ('). Use this for normal HTML escaping and XSS prevention.
  • Encode All Characters: This method converts every single character, including letters and numbers, into numeric HTML entities (like &#72; for 'H'). Use this when you need to obfuscate text or ensure absolute character safety in email templates or special HTML contexts.

When Should You Use HTML Entity Encoding?

  • Displaying Code Examples: When showing HTML, JavaScript, or XML code snippets on your web pages, encode them to prevent the browser from interpreting them as actual code
  • XSS Attack Prevention: Always encode user-generated content before displaying it on your website to prevent malicious script injection
  • Special Character Display: Display special symbols, foreign language characters, and mathematical symbols that might not render correctly otherwise
  • Email Template Development: HTML email clients have varying character support; entities ensure consistent display across all email platforms
  • Form Input Security: Encode form submissions that will be displayed back to users to prevent XSS vulnerabilities
  • Meta Tags and Attributes: Encode special characters in HTML attributes and meta tags
  • Database Storage: Encode HTML before storing in databases to prevent SQL injection combined with XSS attacks

Why Use Our HTML Entity Encoder Tool?

  • Completely Free: No registration, no limits, no payments - use our HTML encoder as often as needed
  • Maximum Privacy: All encoding happens in your browser using JavaScript - your HTML code never reaches our servers
  • Instant Results: Real-time encoding and decoding with zero server delays
  • Two Encoding Modes: Choose between standard entity encoding or complete character encoding
  • Security-Focused: Perfect for preventing XSS attacks and securing user-generated content
  • Developer-Friendly: Clean interface designed specifically for web developers and HTML coders
  • Mobile Compatible: Works flawlessly on all devices including smartphones and tablets
  • No Software Required: Use directly in your web browser, no downloads or installations needed

Named Entities vs Numeric Entities

HTML entities come in two formats: named entities (like &copy;) and numeric entities (like &#169;). Named entities are easier to read and remember, making them ideal for common characters. Numeric entities work for any Unicode character and are supported more universally across older browsers and email clients. Our tool uses named entities for the five special HTML characters and can generate numeric entities for all characters when you use the "Encode All Characters" option.

HTML Entity Encoding for Security (XSS Prevention)

One of the most critical uses of HTML entity encoding is preventing Cross-Site Scripting (XSS) attacks. When you display user-generated content on your website without encoding it first, malicious users can inject JavaScript code that executes in other users' browsers. By encoding HTML entities, you convert potentially dangerous characters like < and > into safe entity codes, preventing the browser from interpreting them as HTML tags or JavaScript code. This is a fundamental security practice for all web applications that handle user input.

Frequently Asked Questions About HTML Entities

What's the difference between HTML entities and HTML escape sequences?
They're the same thing! HTML entities, HTML escape codes, and HTML escape sequences all refer to the same concept of using special codes to represent characters in HTML.

Do I need to encode all special characters in HTML?
At minimum, you should always encode the five special HTML characters: < > & " '. For maximum compatibility and security, encode any character that might cause issues in your specific context.

Will HTML entity encoding slow down my website?
No. Modern browsers decode HTML entities instantly. The minimal processing time is negligible compared to the security and compatibility benefits you gain.

Can I use HTML entities in JavaScript strings?
HTML entities work in HTML content, not JavaScript strings. For JavaScript, you need JavaScript escape sequences. However, you can use HTML entities in strings that will be inserted into HTML via JavaScript.

Should I encode HTML entities in JSON data?
Generally no. JSON has its own escaping mechanism. Only encode HTML entities when the JSON data will be directly rendered as HTML on the client side.

Are HTML entities case-sensitive?
Named entities ARE case-sensitive (&copy; works, &COPY; doesn't). Numeric entities are not case-sensitive for the hexadecimal prefix (&#x or &#X both work).

How do I display the ampersand character in HTML?
Always use &amp; to display an ampersand in HTML. Never use a raw & symbol as it may be interpreted as the start of an entity code.