HTML Encoder & Decoder Online Free
HTML Encoder / Decoder is a free online tool that converts special characters to HTML entities (< > & " ') and back — instantly in your browser. It is useful for safely embedding user content in HTML pages, debugging entity-encoded markup, and preventing XSS vulnerabilities. Nothing is sent to a server.
Frequently Asked Questions
What is HTML encoding?
HTML encoding converts characters that have special meaning in HTML — such as <, >, &, and " — into their entity equivalents (< > & "). This prevents browsers from interpreting them as HTML markup and is essential when displaying user-submitted content on a web page.
Why is HTML encoding important for security?
Failing to encode user input before rendering it in HTML is the root cause of Cross-Site Scripting (XSS) attacks. If a user submits <script>alert(1)</script> and it is inserted into the page without encoding, the script executes. Encoding it to <script> makes it display as literal text instead.
What does "Encode for attribute" do?
Attributes in HTML tags require additional characters to be encoded. The backtick (`) and equals sign (=) can be used in attribute injection attacks. The "Encode for attribute" option additionally encodes ` to ` and = to =, making the output safe to insert inside an HTML attribute value.
What entities does this tool encode and decode?
The tool handles the five core HTML entities: & (ampersand), < (less-than), > (greater-than), " (double quote), and ' (single quote / apostrophe). In attribute mode it also handles ` (backtick) and = (equals sign). The entity count is shown below the output.
Is my data sent to a server?
No. All encoding and decoding is done with plain JavaScript string replacement in your browser. Nothing is sent to any server. The tool works offline once the page has loaded.