HTML to JSX Converter

What Is JSX — and Why Is It Different from HTML?

JSX (JavaScript XML) is a syntax extension for JavaScript that lets you write HTML-like markup directly inside JavaScript code. Introduced by Facebook (now Meta) as part of the React library in 2013, JSX compiles into standard JavaScript function calls — specifically, React.createElement() calls (or in React 17+, the new JSX transform). It is the primary way React developers describe the structure and appearance of UI components.

Although JSX closely resembles HTML, it is not HTML. The two share the same angle-bracket tag syntax and nesting model, but JSX is JavaScript-first — which means it must conform to JavaScript rules rather than HTML rules. This creates a specific set of incompatibilities that make it impossible to paste raw HTML directly into a JSX file without modifications. Every developer who has tried copying HTML from a design tool or a web page into a React component has encountered the resulting syntax errors.

The transformations required to convert valid HTML into valid JSX are well-defined and systematic — which is exactly why automated conversion tools like this one are so valuable. Understanding why each transformation is necessary also makes you a better React developer, because the same rules apply every time you write JSX by hand.

How the HTML to JSX Converter Works

Our converter applies a comprehensive set of transformations to raw HTML input, producing syntactically valid JSX output. Unlike simple search-and-replace tools, it uses a structured parsing approach that correctly handles nested attributes, multi-value inline styles, complex event handler expressions, and edge cases that naive regex substitution gets wrong.

className and htmlFor: The Most Common JSX Gotchas

The two most frequently encountered HTML-to-JSX conversion issues are class → className and for → htmlFor. Both exist for exactly the same reason: these words are reserved in JavaScript.

class is a reserved keyword in JavaScript for defining classes (ES6+). Using it as a JSX attribute would create a parsing ambiguity. React's team solved this by using className, which mirrors the DOM property name (element.className). Similarly, for is a reserved word in JavaScript loops, so htmlFor is used instead. React will warn in the browser console if you use the HTML versions, but the component will still attempt to render — which is why these mistakes can be hard to notice without careful attention.

Self-Closing Tags: JSX's Strictest Requirement

HTML is forgiving about void elements — tags like <br>, <img>, <input>, and <meta> don't need closing tags in HTML5. JSX has zero tolerance for this: every element must either be explicitly closed with a closing tag (<div></div>) or self-closed with a trailing slash (<input />). An unclosed void element in JSX will produce a compilation error that prevents the entire application from running.

The complete list of void HTML elements our converter self-closes: area, base, br, col, embed, hr, img, input, link, meta, param, source, track, wbr.

Inline Styles: From CSS Strings to JavaScript Objects

HTML inline styles use a CSS string syntax. JSX inline styles use a JavaScript object with camelCased property names. This is one of the more complex transformations because it requires both parsing the CSS string into individual property-value pairs and converting CSS property names to their camelCase JavaScript equivalents.

The double curly braces in JSX style props look confusing at first but make perfect sense: the outer braces { } tell JSX "evaluate this as a JavaScript expression," and the inner braces { } are the JavaScript object literal containing the style properties.

camelCase Attribute Names: The Complete Rule Set

JSX follows the DOM property naming convention rather than the HTML attribute naming convention. Where HTML uses hyphenated or lowercase attribute names, JSX uses camelCase equivalents that match the JavaScript DOM property names. This applies to a significant number of commonly used attributes.

Event Handlers: From HTML Strings to JSX Functions

HTML event handlers are strings containing JavaScript code (onclick="handleClick()"). JSX event handlers are camelCased and expect JavaScript function references (onClick={handleClick}). This is a fundamental architectural difference — HTML executes a string as code, JSX passes a function reference that React calls when the event fires.

All standard DOM event handlers are converted: onclick→onClick, onchange→onChange, onsubmit→onSubmit, onfocus→onFocus, and all others. The handler function name is extracted from the HTML string, and the parentheses are removed to produce a function reference rather than an immediate call.

Who Benefits from an HTML to JSX Converter?

Pro Tips for Getting the Best Results from the HTML to JSX Converter