You can write and typeset LaTeX right now, in nothing but a web browser — no install required. A pane for your source sits beside a live preview of the finished PDF, and one button compiles it, so you get to try LaTeX itself before wrestling with an installation. This page surveys the main online editors (Overleaf, Cloud LaTeX, Papeeria, and others), how to choose between them, and how they differ from a local setup.
The shortest path: a browser
An online LaTeX editor keeps the TeX engine, the packages, and the fonts all on a server; your browser just uploads the source and displays the PDF that comes back. So there is nothing to install or configure locally, and it behaves the same on a shared university PC, a tablet, or a borrowed laptop. From the moment you create an account, you are working in a complete environment with thousands of packages already in place.
Most editors put the source on the left and the PDF on the right; you edit the body, press “Recompile,” and the preview updates. To see it work — equations and all — paste this minimal document in and compile it:
\documentclass{article}
\begin{document}
Hello from the browser! Here is an equation:
\[ \int_0^1 x^2 \, dx = \frac{1}{3} \]
\end{document}People stay on online editors for two big reasons. First, there is no environment to maintain — updates and package installs all happen on the server. Second, collaboration is easy: opening one manuscript and writing in it together, in real time, is something a local setup cannot match without effort. Here are the main services in turn.
Overleaf — the de facto standard
The most widely used online LaTeX editor today is Overleaf. The mathematicians John Hammersley and John Lees-Miller began building it as WriteLaTeX in 2011, launched a public beta in 2014, and renamed it Overleaf in 2015. In July 2017 they merged with the rival ShareLaTeX, producing Overleaf v2 with a combined community of over two million users. ShareLaTeX’s strong Git/GitHub integration and real-time editing joined Overleaf’s large template library and beginner-friendly interface in a single product.
Even a free account gives you unlimited projects, real-time editing shared with one collaborator, hundreds of templates for journals, CVs, and theses, a toggle between a “Code Editor” and a rich-text “Visual Editor,” and in-document comments. By default it runs TeX Live 2025 (Overleaf adopts each new release a few months after it ships), and for reproducibility you can pin an older TeX Live — back to 2016 — in a project’s settings.
There are free-tier limits worth knowing. The compile timeout is 10 seconds, so a long thesis or a heavy TikZ build can exceed it and time out, and the version history is not included on the free plan. Paid plans raise the timeout to 240 seconds, allow 10 collaborators on Standard/Student (unlimited on Pro), and add full labelled history, track changes, Git/GitHub/Dropbox sync, and reference-manager integration (Zotero, Mendeley).
Japanese takes one extra step. Overleaf defaults to the pdfLaTeX engine, which cannot set Japanese, so typing Japanese with no setup gives an error or garbled output. The simplest fix is to switch the Compiler to LuaLaTeX in the menu and use the ltjsarticle class (it loads luatexja for you). To use the pLaTeX workflow common in Japanese journals, set the Compiler to “LaTeX” and add a latexmkrc that calls platex and dvipdfmx. Our Overleaf page walks through the details.
% Overleaf: メニュー → Compiler → LuaLaTeX に設定
\documentclass{ltjsarticle}
\begin{document}
こんにちは、\LaTeX！数式も書けます: $e^{i\pi}+1=0$
\end{document}Cloud LaTeX — Japanese works out of the box
Cloud LaTeX is a Japan-made service run by Acaric. It launched in beta in 2014 and as an official product in 2016, and has tens of thousands of registered users. Its defining feature is that Japanese typesets with no configuration — open a project, type Japanese, compile, and it comes out correctly. There is no engine to switch and no latexmkrc to write, as on Overleaf; the single most common stumbling block for Japanese simply isn’t there.
It is feature-rich, too: more than 100 templates (including the Grant-in-Aid “科研費 LaTeX” form and many conference and journal styles), bundled copies of common .sty files, the latest TeX Live, Dropbox sync that preserves your folder hierarchy (so you can work locally alongside it), an extension to edit in VS Code instead of the browser, plus autosave, file versioning and restore, drag-and-drop upload, and ZIP export. Since 2024 it can also issue public read-only links that let anyone view and download the PDF or source. It is free to use.
If your writing is mostly in Japanese, Cloud LaTeX is an easy pick. Its collaboration, though, is built around share links and Dropbox sync rather than Overleaf-style live multi-cursor co-editing — so for many authors writing at once, Overleaf is a step ahead, while for turnkey Japanese, Cloud LaTeX leads.
Papeeria and other options
Papeeria has a permanent free tier with unlimited public projects, real-time collaboration, BibTeX, and Git/GitHub integration; you can mix Markdown into your LaTeX, and it auto-compiles in the background. The catch is that the free tier allows only one private project — paid plans, from a few dollars a month, raise the private-project count and upload limits. It suits work that can be public, or team projects.
Around these sit further choices. CoCalc bundles a LaTeX editor into a scientific-computing workspace alongside Jupyter and SageMath; TeXpage foregrounds encryption; Authorea aims at the whole write-to-submit publishing workflow. A newer category compiles entirely inside the browser via WebAssembly — no server round-trip, works offline, and no server-side timeout — though its package coverage is still narrower than a full TeX Live and the approach is maturing.
Online or local?
The strengths of going online are that there is nothing to set up, nothing to maintain, the same environment on every device, and genuinely easy collaboration. For a first document, a class assignment, or co-writing a paper, that is usually all you need.
A local install wins in other situations. Free tiers cap compile time (10 seconds on Overleaf), so a long thesis or a heavy figure can time out; a network connection is assumed; and your source lives on someone else’s server, which can matter for unpublished or confidential research. Pinning exact package and font versions is also harder. A local setup removes the timeout, works offline, keeps files on your own disk, and lets you pin or patch any package freely.
The recommendation: start online to get comfortable with LaTeX itself, then move to a local TeX Live or MiKTeX install once you need control, scale, or privacy. Or have it both ways — sync cloud and local, as with Cloud LaTeX + Dropbox or Overleaf + Git.