AO3 offers downloads in AZW3, EPUB, MOBI, PDF, and HTML formats. Of these, HTML should be your primary archival tool. Here's why:
- PDF sucks: PDFs lock you into a static page and font size, and are a pain to extract the original text from if you need to convert to an editable form.
- EPUB, MOBI, and AZW3 just HTML under the hood: Most eBook formats are just a wrapper around zipped HTML but, again, with extra steps to get at the underlying content. AO3 also compresses images before insertion into ereader formats, so image-heavy fics/comics may not render correctly
- HTML is resilient: HTML can, in a worst case, be read as plaintext, and still retain readability and structure.
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HTML is flexible: HTML, and especially AO3's
restricted subset of HTML, is future-proof, easy to edit by
hand, and can be trivially copied to other platforms or
converted to MarkDown, Google Docs, EPUB/MOBI/AZW3, etc. via
many free tools (conversion websites,
pandoc, etc.). - HTML works anywhere: HTML is viewable on all devices, accepts custom font size and color overrides for accessibility, and works with screen readers. All major eReaders accept HTML natively (including Send to Kindle), and those with more stringent format needs will trivially find a converter for the world's most popular web file format.
