Free online ASCIIDOC to PDF converter

What the ASCIIDOC format is

AsciiDoc is a plain-text markup format for structured documents such as software manuals, README files, books, articles, and technical specifications. Authors write readable source files with headings, lists, delimited code blocks, tables, attributes, cross-references, and optional extensions; common filename extensions are .adoc and .asciidoc.

AsciiDoc files are commonly created in text editors, integrated development environments, documentation repositories, and systems that use Asciidoctor or the original AsciiDoc processor. The source remains editable and version-control friendly, but its final appearance depends on the converter, theme, fonts, image assets, and document attributes.

What the PDF format is

PDF stores pages with their layout, fonts, graphics, and printable dimensions preserved across operating systems. It suits formal documentation, email attachments, printing, records, and review because recipients generally do not need the source editor or AsciiDoc toolchain.

PDF is less convenient than AsciiDoc for editing and automatic version comparison. It can also be larger than the source file, particularly when it embeds fonts or high-resolution images.

How to convert ASCIIDOC to PDF

The most direct command-line method is Asciidoctor PDF, the PDF converter for the Ruby-based Asciidoctor toolchain.

1. Install Ruby if it is not already available.
2. Install the converter with gem install asciidoctor-pdf --pre. The --pre option may be needed for the current prerelease package; omit it when installing the latest stable release.
3. Open a terminal in the directory containing the source file and run asciidoctor-pdf manual.adoc -o manual.pdf.
4. Open manual.pdf in a PDF viewer and check page breaks, tables, code blocks, links, and images.

For a source file that references images or includes other AsciiDoc files, run the command from the document’s project directory and preserve its relative folder structure. Use -a toc=left or -a toc=macro to add a table of contents, and -a pdf-theme=custom-theme.yml to apply a custom PDF theme. A title, author, and revision can be set in the document header with attributes such as = Installation manual, Author Name <author@example.com>, and :revnumber: 1.2.

You can also convert the file for free on the 101convert.com website without installing software. Upload the AsciiDoc file, choose PDF as the output format, start the conversion, and download the generated document.

Quality and compatibility considerations

AsciiDoc syntax is processed by a converter rather than copied directly into PDF, so unsupported extensions, custom macros, include paths, and conditional content can change the result. Asciidoctor PDF uses the current working directory and document attributes to resolve includes and assets; missing paths produce incomplete output or warnings.

For predictable pagination, embed or explicitly configure fonts, set the page size and margins in a PDF theme, and use print-oriented image dimensions. Check diagrams, SVG files, external links, footnotes, table overflow, and right-to-left or non-Latin characters after conversion. A source file can convert successfully while still producing clipped tables or missing glyphs if the selected font lacks required characters.