What Is HTML Entity Encoder / Decoder?

A free online HTML entity encoder and decoder. Convert special characters like <, >, &, " to their HTML entity equivalents (&lt;, &gt;, &amp;, &quot;) and back. Essential for preventing XSS attacks and debugging HTML output.

HTML entities are special character sequences that represent characters with special meaning in HTML markup. Characters like <, >, &, " and ' must be encoded as &lt;, &gt;, &amp;, &quot;, and &#039; respectively when they appear in HTML content — otherwise, the browser interprets them as markup rather than text. HTML Entity Encoder/Decoder handles both encoding and decoding of these entities in a bidirectional interface.

In Encode mode, the tool scans your input text for the five core HTML special characters and replaces each one with its corresponding entity. This is essential when you need to display code snippets on a web page, accept user-generated content safely, or prepare text for inclusion in HTML templates. Without encoding, a user submitting the text "<script>alert('xss')</script>" would cause the browser to execute the script as code rather than displaying it as text.

In Decode mode, the reverse operation converts entity-encoded text back to its human-readable form. This is useful when debugging HTML output, reading raw HTML source from web pages, or processing data from HTML-based APIs. The tool also handles &nbsp; (non-breaking space), which is commonly encountered in web content but is invisible in rendered HTML.

The syntax-highlighted output makes it easy to distinguish encoded characters from regular text. Encoded entities appear highlighted so you can verify that all special characters were properly converted. The swap button reverses the conversion direction instantly, supporting workflows where text goes through multiple encode-decode cycles during development and debugging.

Real-World Use Cases for HTML Entity Encoder / Decoder

Sanitizing User-Generated Comments for a Blog

A blog comment contains <script> tags and HTML formatting. Paste the comment text through the encoder in Encode mode. All <, >, and " characters become safe entities. The encoded text can then be safely rendered in the blog HTML without risk of XSS attacks or broken page layout from unescaped tags.

Debugging HTML Output from a Template Engine

Your server-side template is producing output like "Hello &lt;b&gt;World&lt;/b&gt;" and you need to see the decoded version. Paste it into Decode mode to get "Hello <b>World</b>". This helps you verify that the template engine is correctly escaping user input before rendering.

Preparing Code Snippets for a Developer Blog

You are writing a tutorial about JavaScript and need to show code that includes angle brackets. Write the code example in normal text, run it through Encode mode, and paste the encoded result into your blog's HTML editor. The code displays correctly without being interpreted as HTML.

Why Use HTML Entity Encoder / Decoder?

  • Bidirectional: encode and decode HTML entities
  • Syntax-highlighted output for easy reading
  • Handles &amp;, &lt;, &gt;, &quot;, &#039;, &nbsp;
  • One-click swap to reverse direction

How to Use HTML Entity Encoder / Decoder — Step by Step

1

Choose mode: encode or decode.

2

Paste your text or HTML entities into the input.

3

The output updates instantly with syntax highlighting.

4

Copy or download the result.

Who Is HTML Entity Encoder / Decoder Best For?

  • XSS prevention
  • HTML debugging
  • template escaping
  • content sanitization

Pro Tips for HTML Entity Encoder / Decoder

  • 1Never trust user input that contains raw HTML special characters. Always encode &, <, >, ", and ' before rendering user-submitted content on a web page.
  • 2The decode mode is useful for reading HTML email source code. HTML emails often use heavy entity encoding, and decoding makes the content readable for debugging.
  • 3If you see "&amp;" displayed on a website instead of "&", it means the text was double-encoded. Run it through Decode mode once to resolve it.
  • 4For content management workflows, encode text at the point of input (when the user submits) and decode at the point of display only if needed. Storing encoded text in the database prevents XSS issues.

HTML Entity Encoder / Decoder — Frequently Asked Questions

Why do I need to encode HTML entities?

Encoding HTML entities prevents browsers from interpreting special characters as HTML markup. This is essential for displaying code snippets and preventing XSS attacks in user-generated content.

What entities does this tool handle?

It handles the five core HTML entities: & (&amp;), < (&lt;), > (&gt;), " (&quot;), and ' (&#039;), plus &nbsp; for non-breaking spaces.

Can I use these tools with sensitive/proprietary data?

Absolutely. All processing runs locally in your browser with zero server uploads. This makes these tools safe for proprietary code, internal API keys, and confidential data.

Do these tools work offline?

Yes, once the page has loaded, most developer tools continue functioning without an internet connection. This makes them ideal for air-gapped environments or travel.

What browsers are supported?

All modern browsers are supported: Chrome, Firefox, Safari, and Edge. Internet Explorer is not supported. The tools leverage modern JavaScript APIs like Web Crypto, TextEncoder, and BigInt.

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