LaTeX editor

Test version. Compilation (pdfLaTeX, TeX Live 2026) runs in your browser: nothing is sent to a compilation server. The first compilation may be a little slow (from a few seconds to a minute depending on your connection): it downloads the engine, about 20 MB, once, then kept in the browser cache. Later compilations take a few seconds.

Compile, go from the PDF to the code

• Compile: Ctrl+Enter. References, table of contents and bibliography update automatically (extra passes when needed).
• From the PDF to the code: double-click in the PDF, the editor opens the file at the matching line (also in the separate preview window ⧉).
• From the code to the PDF: double-click in the code (or the “⇥ PDF” button, or Ctrl+Shift+Enter), the matching place is highlighted in the PDF.
• Missing package: Otoolia's TeX Live selection has the common packages (beamer, TikZ, pgfplots, tcolorbox, French babel, fourier, bclogo…). For a personal or rare package, add its .sty (or .cls) file to the project, in any folder: it is used at the next compilation.

Open a GitHub repository

1. Create a private repository on GitHub (for example latex-courses), empty or with your files.
2. Create a fine-grained token: Repository access → Only select repositories → your repository; Permissions → Contents: Read and write. Copy the token.
3. In the editor: Open a GitHub repository, paste the token and the repository name (account/latex-courses).

The token stays in this browser and is only sent to GitHub. Each sync (Ctrl+S) creates a commit: GitHub keeps the history of all your versions. If a file was changed elsewhere in the meantime, the editor asks which version to keep.

Organise a course with subfiles

Put the shared preamble at the root of the repository (preambule-cours.tex) and each chapter in a folder, starting with \documentclass[../preambule-cours.tex]{subfiles}. “This file” compiles the open chapter alone, “Whole document” compiles the main file. The “Course” template sets this up.

Writing aids

• Autocompletion: commands and environments of LaTeX and of the loaded packages, your own macros and boxes (read from the preamble), labels after \ref{, references after \cite{, files after \input{ or \includegraphics{. Tab moves between fields.
• Checks while typing: braces, \begin without \end, duplicate labels, missing references and files.
• Formula preview under the cursor, with your macros.
• Document outline (sections, slides, definitions and theorems), project-wide search (Ctrl+Shift+F), quick open (Ctrl+P), Ctrl+click to jump to a macro definition or to the label of a \ref.
• French spelling and grammar (“abc✓” button): the written text is checked by Grammalecte, without commands or formulas. Red underline: spelling; blue: grammar. Click an underlined word for suggestions, to ignore it or add it to the dictionary (kept in this browser).

Compilation: BusyTeX (TeXlyre), AGPL-3.0 licence, and TeX Live 2026 (each package under its own free licence); spelling and grammar: Grammalecte (GPL-3.0); formulas: KaTeX (MIT); PDF: pdf.js (Apache 2.0); archives: JSZip (MIT). The editor's code, under the AGPL-3.0 licence, is served as is, neither minified nor obfuscated, in assets/outils/editeur-latex/.