HTML Entity Encoder/Decoder
Encode and decode HTML entities for safe web content.
HTML Entities
HTML entities let you display characters that have special meaning in HTML. < becomes <, > becomes >, and & becomes &. Otherwise, the browser would interpret them as HTML tags or entity markers.
Entities also help with characters that might not exist in your document's encoding, like © (©) or ™ (™). Though with UTF-8 being universal now, you can often just type these directly.
Essential Entities
<for < (less than)>for > (greater than)&for & (ampersand)"for " (double quote) for non-breaking space
Understanding HTML Entities
HTML entities represent special characters that have meaning in HTML syntax. For example, < represents "<" because the actual less-than symbol would be interpreted as a tag opening. Common entities include & (&), < (<), > (>), " ("), and ' (').
Entities can be named (like &) or numeric (& or &). Numeric entities can represent any Unicode character, while named entities are limited to predefined characters. HTML5 defines over 2,000 named entities including mathematical symbols and special characters.
Frequently Asked Questions
Why are HTML entities important for security?
Without encoding, user input containing < or> could inject malicious scripts (XSS attacks). Encoding converts these to harmless < and > that display correctly but don't execute. Always encode user-generated content before displaying it.
What's the difference between named and numeric entities?
Named entities like © are readable but limited to predefined characters. Numeric entities like © work for any Unicode character. Use named entities for common characters (easier to read) and numeric for special symbols.
When should I decode HTML entities?
Decode when extracting plain text from HTML for analysis, indexing, or display in non-HTML contexts. Common use cases include preparing content for APIs, text analysis, or displaying HTML-encoded database content in plain text.
Do I need to encode all characters?
No. Only characters with special meaning in HTML need encoding: <> & " and '. Regular letters, numbers, and most punctuation can be used directly. However, encoding everything is safer when dealing with user input or untrusted content.
When You Actually Need This
Special characters in HTML need encoding to display correctly. If you're writing documentation or a tutorial that needs to show <div> or as literal text, those characters have to be converted to <div> and &nbsp; or the browser tries to interpret them as markup. This is especially tricky with user-generated content — if someone types "I use <script> tags in my code" in a comment field and you display it without encoding, it breaks your page layout or creates XSS vulnerabilities.
Emails and plain text rendering are another common problem. HTML email clients need entities for special characters, and if you're generating emails programmatically, any quotation marks, ampersands, or mathematical symbols in the content need entity-encoding. A subject line like "Q&A for Smith & Sons" will break email parsing unless the ampersands are encoded as &. The reverse also matters — if you receive HTML content and need to extract plain text for a preview or notification, decoding entities converts © 2024 back to © 2024 so it reads naturally.