&, <, >, and quotes — to their HTML entity equivalents.HTML entity encoding replaces characters that have special meaning in HTML — such as <, >, and & — with safe escape sequences like <. This prevents XSS injection, fixes rendering bugs, and is essential when embedding user-supplied text inside HTML. The converter runs client-side: your content is never transmitted to a server.
You need entity encoding whenever you are inserting dynamic text into an HTML template. Without it, a value like <script>alert(1)</script> becomes executable JavaScript. The decoder is equally useful: raw HTML source downloaded from a site often contains encoded entities that need to be read back as their original characters for further processing.
& < > " ' — all five XSS-relevant characters , ©) and numeric references (©)HTML encoding replaces characters with named or numeric entities for safe use inside HTML markup. URL encoding (percent-encoding) encodes characters for safe use inside URIs. They use completely different escape sequences — < vs %3C for the same < character.
At minimum: & (as &), < (as <), and > (as >). Quotes " and ' should also be encoded when the text appears inside an attribute value.
Yes — this tool encodes literally, so < would become &lt;. Always decode first if your input might already be encoded, then re-encode cleanly.
All processing happens in your browser's JavaScript engine. Nothing is sent to any server, making it safe for any content including credentials or private text.
See also HTML Decoder, HTML Formatter, and the full encoding toolkit at Chunky Munster.