Can KaTeX alone create a PDF from a LaTeX document?

No. KaTeX is a rendering library for displaying mathematical expressions on the web. It does not replace LaTeX's role in processing chapters, sections, citations, packages, and other document-wide elements to typeset a complete document.

Do all LaTeX equations work unchanged in KaTeX?

Not always. KaTeX uses LaTeX-like mathematical syntax, but it does not support every command, environment, package, or advanced macro. You should check whether the expressions you intend to use are supported.

Can I use LaTeX and KaTeX together for a website?

Yes. For example, you can typeset a paper or textbook manuscript with LaTeX while using KaTeX to display selected equations from the same content in separate web documents or course pages. However, you need to verify equation syntax compatibility separately.

What do KaTeX error messages mean?

They usually mean that the input math string has invalid syntax or uses a command that KaTeX does not support. Depending on the configuration, KaTeX can show the original input instead of displaying an error.

Are dollar-sign equations in Markdown automatically KaTeX?

No. Conventions such as dollar signs may be used to write math, but the Markdown service or website's connected renderer is what actually interprets and displays it. Whether that renderer is KaTeX, and which syntax it permits, depends on the environment's configuration.

What Is the Difference Between LaTeX and KaTeX?

By 쉬었음.comPublished September 12, 2026

LaTeX is a system for writing and typesetting entire documents, such as papers, textbooks, and reports, while KaTeX is a JavaScript library that renders LaTeX-style mathematical expressions on web pages. Because both use similar math syntax, they can appear to be the same kind of tool, but they differ in what they process, what they produce, and how they are installed and operated. If you need a finished document centered on PDF output, LaTeX is the natural first option to consider. If you want to display equations clearly on the web or in Markdown, start by considering KaTeX. www.latex-project.org github.com

What Is LaTeX?

LaTeX is a document writing and typesetting system for high-quality output. Typesetting means arranging document elements—such as text, equations, paragraphs, pages, headings, tables, and figures—in a readable form to produce a finished document. Rather than usually dragging individual characters into place on screen, users write commands that describe the document's structure and meaning. A processing program then typesets the document from that input. The LaTeX Project distributes LaTeX as free software. www.latex-project.org

For example, an author marks in the manuscript that “this sentence is a section heading,” “this item is an equation,” or “this figure is referenced.” LaTeX then produces a document that matches that structure, including numbering, margins, line breaks, and equation placement. The key is to express the roles and relationships within the document rather than manually specifying the visual position of every character.

LaTeX covers much more than a single equation. It can handle interconnected elements in long documents, including headings and body text, chapters and sections, lists, tables and figures, citations, bibliographies, indexes, and cross-references. This often makes it suitable for documents where format and structure matter, such as academic papers, technical reports, books, and course materials. www.latex-project.org www.latex-project.org

In this context, saying that you “write a document in LaTeX” means more than using notation such as \frac in equations. It refers to the full process of creating a manuscript that includes the beginning and end of the document, its body structure, and the relationships among document elements, then passing it through a document-processing workflow to obtain typeset output.

What Is KaTeX?

KaTeX is a JavaScript-based library for displaying mathematical expressions in web environments. A library is a software component designed for other web pages or applications to load and use for a specific capability. In KaTeX's case, that capability is interpreting TeX/LaTeX-style math strings and converting them into a form that can be displayed within a web page. github.com

For example, suppose a web page's source contains an equation such as $E=mc^2$ or \frac{a}{b}. KaTeX can take that input and render the result into the DOM, the browser's document structure. The DOM is the way a browser represents elements such as page headings, paragraphs, and buttons as an object structure. KaTeX can also pre-generate HTML strings for equations in server-side JavaScript environments. github.com katex.org

An equation displayed on the web is not just a line of text. It must represent the layouts required by mathematical notation, such as fraction bars, superscripts and subscripts, root symbols, and matrices. To do this, KaTeX generates HTML and MathML-style markup and uses CSS and font files for visual appearance. In other words, using KaTeX solves the problem of displaying equations within a web document; it does not mean typesetting an entire web page as a LaTeX document. github.com

Why Are the Two Tools Often Confused?

The main reason is that their input syntax looks similar. Commands used to write equations in LaTeX are also commonly used as KaTeX input on the web. For example, the following equation is familiar in both contexts.

E = mc^2

Fractions and subscripts are also written like this.

\frac{x^2 + y^2}{r} \quad\text{and}\quad a_n

However, accepting an equation string with the same appearance does not mean the tools have the same scope. LaTeX focuses on the structure and typesetting of an entire document, whereas KaTeX focuses on displaying mathematical expressions embedded in that document or web content. “Can use LaTeX syntax” and “can compile a LaTeX document” are different statements. www.latex-project.org github.com

The results users see can also feel similar. A PDF created with LaTeX has beautiful equations, and a web page using KaTeX can also have beautiful equations. But in the first case, equations are part of the typesetting of a finished document; in the second, they are a feature for displaying equations in a browser. Distinguishing the tools by the unit of work they perform rather than by the appearance of the output reduces confusion.

How Do Input, Processing Environment, and Output Differ?

The most practical way to compare the two tools is to ask: “What do you input, where is it processed, and what do you get?”

Category	LaTeX	KaTeX
Primary focus	Entire document	Mathematical expressions
Typical input	A document manuscript containing titles, body text, chapters and sections, tables, figures, citations, and equations	Math strings to embed in a web page or application
Processing environment	A LaTeX distribution and document-processing engine	A browser or server-side JavaScript environment
Main output	A typeset finished document, often in a PDF-centered workflow	HTML and MathML-style markup for equations embedded in a web page, along with styling output
Typical use cases	Papers, reports, textbooks, and books	Blogs, web apps, Markdown-based documents, and online course pages

In a LaTeX workflow, the entire manuscript is processed. It can manage information that connects multiple parts of a document, such as tables of contents, section numbers, figure numbers, and references within the document. Think of how related numbering and references can be organized according to the document structure when you change a heading or add an item in one place. This is a broader scope than a tool responsible only for displaying one equation. www.latex-project.org www.latex-project.org

KaTeX, in contrast, generally renders the equation portions of an already existing web document. Examples include changing only an equation in a body paragraph, displaying a mathematical expression entered by a user, or making equation blocks visible in a Markdown-written article. KaTeX itself is responsible for displaying math on the web; it is not generally expected to automatically handle functions such as post management, document table-of-contents construction, or bibliography data management. github.com katex.org

When Should You Choose LaTeX?

If the final deliverable is a self-contained finished document, such as an academic paper PDF, technical report, textbook manuscript, or book, it aligns well with LaTeX's purpose. As a document gets longer, consistency across the entire document becomes more important: heading hierarchies, chapter and section organization, numbering for tables and figures, equation numbers, citations and bibliographies, and internal references. LaTeX is designed for this kind of structured document writing and typesetting. www.latex-project.org www.latex-project.org

For example, if a research report contains many links such as “see Table 2,” “use the definition in Equation 4,” and “refer to the appendix below,” the central issue is not merely how the equations look. What matters is how to structure and typeset the document's many elements. In this case, displaying only equations with KaTeX does not fully cover the required scope of work.

LaTeX's approach to document writing can feel unfamiliar at first. Instead of immediately adjusting the desired result by hand on the screen, you write commands and structure, process the result, and review it. However, if the document format and structure are stable and you repeatedly create similarly structured documents, this characteristic can be helpful. Conversely, if the main task is quickly revising a short notice while immediately editing the appearance of each paragraph, LaTeX's document typesetting capabilities may be more than you need.

When Should You Choose KaTeX?

If you want to include equations in content read in a browser—such as web pages, blog posts, web applications, or online lessons—KaTeX has a clear role. You can build the page body with standard web technologies or a content system and have KaTeX render only the parts that require mathematical notation. github.com katex.org

For example, you may want to show an expression like the following on a calculus learning page.

\int_a^b f(x)\,dx

If the goal is for learners to read the equation in a browser, a tool that displays mathematical notation through HTML is a more direct solution than a tool for typesetting an entire textbook as a PDF. KaTeX supports both rendering in the browser and generating result strings on the server to include in a web response. katex.org katex.org

It is easy to think that using KaTeX ends with preparing equation input, but actual display also requires CSS and fonts. The site or application must also decide which elements count as math, how to distinguish inline math from separate display-math blocks, and how to show invalid input. KaTeX provides math rendering, but it does not prescribe a single set of content-authoring rules or page-integration methods. github.com katex.org

Is KaTeX a Web Replacement for LaTeX?

No. Saying “I want to use LaTeX on the web, so I can use KaTeX” is accurate only in some situations and is inaccurate overall. KaTeX is not a tool that moves the entire LaTeX document system into the browser. It is a math renderer that quickly displays a subset of LaTeX-like mathematical syntax on the web. github.com www.latex-project.org

Therefore, you should not expect KaTeX to process an entire paper by giving it document-start commands such as \documentclass. General LaTeX document capabilities—such as document classes, document packages, bibliography management, and chapter and section structure—are not KaTeX's primary processing targets. The fact that KaTeX displays equations does not mean it accepts a complete LaTeX manuscript and typesets it into a finished document.

Conversely, having LaTeX does not mean that a web math renderer is unnecessary. Content read on the web is displayed within the browser's HTML, CSS, and JavaScript environment. Even if you do not create a separate document with LaTeX, there is still a need to present equations naturally within a web service. KaTeX can be appropriate for that need.

As a simple analogy, LaTeX is closer to a typesetting workshop that creates an entire book, from manuscript structure to page layout, while KaTeX is closer to a component that assembles mathematical expressions in web page sentences into a readable form. The analogy does not explain every detail, but it helps illustrate the difference in their scope.

If Their Math Syntax Is Similar, Are They Fully Compatible?

Not always. KaTeX uses TeX/LaTeX math syntax as input, but that does not mean it supports every LaTeX command, environment, package, or advanced macro. In particular, if an existing LaTeX manuscript depends on features from specific packages or on complex custom-defined macros, you should check whether KaTeX supports those expressions before bringing the equations to the web. github.com katex.org

This difference comes from the distinction between “syntax that looks like LaTeX math” and “every feature available in any LaTeX installation.” The possible range of expression in a LaTeX document can vary according to the packages and macros it uses. KaTeX defines the commands and options it supports within its goal of web math rendering. Therefore, assuming that a copied-and-pasted equation will work identically in every environment can cause problems.

In practice, it is realistic to render short, basic equations first and inspect separately only those that produce errors or look different. For example, simple notation such as fractions, subscripts, and roots is generally within the usual scope of math rendering, while commands supplied by particular packages or complex user-defined commands require separate verification. The important point is not to decide that KaTeX supports an expression merely because it appeared in a LaTeX file.

You should also distinguish between an equation rendering successfully and the original intended meaning being conveyed accurately. Even if a command is processed without an error, a person may need to check whether bracket sizing, alignment, or symbol selection differs from expectations. Small visual differences in equations can affect how they are read, so reviewing the rendered output is especially prudent for educational, research, and technical documents.

What Should You Check When an Error Occurs?

If you provide KaTeX with unsupported input or invalid syntax, it can produce a parse error by default. Parsing is the process of interpreting an input string according to grammatical rules. Errors can have many causes, including a simple typo, an unclosed bracket, incorrect command usage, or an unsupported expression. Depending on its settings, KaTeX also provides an option to display the original input instead of producing an error. github.com katex.org

When resolving an error, it helps to proceed in this order:

First, check that equation delimiters, curly braces, and square brackets are properly matched.
Check whether the commands you used are within KaTeX's supported scope.
Look for package features or user-defined macros imported from a LaTeX document.
If you use a setting that shows the source instead of an error, consider that readers may see a broken equation.
After making changes, check both the equation's appearance and its context on the actual web page.

A source-display setting can help prevent a published page from appearing completely blank. However, you should understand that it does not eliminate the error; it merely exposes input that could not be rendered. If readers need to understand the equation, it may be more appropriate to rewrite it using supported syntax or reorganize the expression in another way rather than only changing the display policy.

Errors can have a different nature on the LaTeX side as well. Because LaTeX processes an entire document, problems can occur across a broader range than math syntax alone, including document structure, references, and package usage. Therefore, first distinguishing whether you are “fixing an equation error” or “fixing a document typesetting error” reduces the chance of choosing the wrong tool or solution.

Can You Use Both Tools Together?

Yes. One person does not have to choose only one. For example, you can manage the print and distribution manuscript for an academic paper or textbook in LaTeX, then use KaTeX to display only the required equations on a web page that introduces the content or in supplementary learning materials. In this case, the tools are not competitors so much as a division of roles for different deliverables. www.latex-project.org github.com

However, using them together raises issues of manuscript reuse and compatibility. Because not every equation in a LaTeX manuscript is guaranteed to render directly in KaTeX, equations intended for the web should be verified in an actual KaTeX environment. In particular, if the manuscript uses separate packages or macros, you may need to simplify web equations and use notation that KaTeX supports. github.com katex.org

The reverse is true as well. Even if you have equation snippets written conveniently for KaTeX on a web page, that alone does not complete an entire LaTeX document. A LaTeX document separately requires a document class, structure, and typesetting rules. Sharing part of the same mathematical language does not automatically mean sharing the same content-management method.

In parallel workflows, the important criterion is not simply “whether to keep a single source,” but “what quality standards each deliverable requires.” For print documents, page and reference consistency may matter most; for web content, browser display and input-error handling may be more immediate concerns. If the goals differ, the review process should differ as well.

What Questions Should You Ask When Choosing a Tool?

The similarity of commands can make the choice difficult. To avoid this, ask about the deliverable and working environment before focusing on syntax.

First, identify the final output. If the main goal is a standalone document for downloading or printing, there is good reason to examine LaTeX's document-typesetting scope. If the goal is to let readers view a few or many equations within browser-based content, KaTeX is a direct option. www.latex-project.org github.com

Second, identify the scope you need to manage. If the document interconnects chapters, sections, figures, tables, citations, bibliographies, and cross-references, a math renderer alone may not be enough. Conversely, if you already have a web page and only need to add equation display, adopting a full document typesetting system is not necessarily required.

Third, assess the complexity of the equations and dependencies in existing manuscripts. It matters whether basic mathematical notation is the main content or whether the content depends heavily on specific LaTeX packages and macros. In the latter case, compare the requirements against KaTeX's support scope in advance and account for the possibility that unsupported input can cause errors. github.com

Fourth, decide how and to whom errors should be shown. In an internal authoring tool, error messages may be better for alerting authors to problems. On a public web page, you need a policy for choices such as showing invalid input as source text or blocking it through pre-publication validation. KaTeX's error-handling options connect to these decisions. katex.org

Fifth, test in the environment readers will actually use. Because CSS and fonts affect KaTeX's web rendering, it is a good idea to verify that equations display as intended on the actual page rather than looking only at code under development. With LaTeX, you should likewise review whether equations, references, and page layout match expectations in the processed document output. github.com www.latex-project.org

What Are Some Common Misconceptions?

The first misconception is that “KaTeX is a lighter version of LaTeX.” The tools do share some mathematical syntax, but KaTeX is not simply a product that reduces all of LaTeX's document features. It is a library that solves the separate problem of web math rendering. Missing this distinction can lead you to adopt only a renderer when you need a document-production tool, or to choose an overly large document workflow when you need web equation display. github.com www.latex-project.org

The second misconception is that “you must learn LaTeX to use KaTeX.” Familiarity with TeX/LaTeX-style math notation helps when writing equations in KaTeX, but you do not need to learn document classes, bibliographies, and the entire typesetting workflow before displaying a single web equation. Conversely, being able to write a few KaTeX equations does not mean you have already learned LaTeX document authoring as a whole.

The third misconception is that “once it renders, there are no compatibility problems.” As content grows and new commands or macros are added, new problems can arise that did not exist before. This is especially important when importing equations from other LaTeX manuscripts, where you need to keep checking whether particular expressions are supported by KaTeX. github.com katex.org

The fourth misconception is that “the visual beauty of the equation output is all that matters when choosing a tool.” Clear equation display is important, but the core choice is whether you need to create an entire document or show equations within web content. You need to consider the output's lifecycle, the environments of authors and readers, and review methods together to choose the appropriate tool.

Conclusion: Treat Document Typesetting and Web Math Display as Separate Tasks

The difference between LaTeX and KaTeX is a difference in roles, not a matter of one being better than the other. LaTeX is a system for typesetting structured manuscripts into finished documents such as papers, reports, and textbooks. KaTeX is a library for displaying LaTeX-style mathematical expressions on the web in browsers or server-side JavaScript environments. www.latex-project.org github.com

Therefore, use LaTeX as the starting point when you need to systematically create and typeset an entire document, and use KaTeX as the starting point when you need to render equations in existing web content. Even when using both together, check KaTeX's syntax support scope and error-handling approach. Distinguishing the scope of the task you want to solve before focusing on syntax is the most practical place to start. github.com katex.org