Large PDF Translator

Large PDF Translator takes on the case that trips up most online document translators: the oversized file. Instead of capping input at a few megabytes, it accepts PDFs as long as roughly 2,000 pages or 400 MB and returns a translated version, making it feasible to work with full technical manuals, legal bundles and academic theses rather than snippets.

The extension focuses on fidelity as well as size. It aims to preserve the original layout, columns and formatting so the translated document remains recognisable and usable, and it includes OCR so scanned, image-only pages are not excluded from translation. Output can be read within the extension or downloaded for offline use, and there is no fixed ceiling on the number of documents you translate.

It covers more than 130 languages, including right-to-left scripts, which makes it useful when target languages go beyond the usual handful. Because the extension is small and installs into Chrome, it fits into an existing document workflow rather than requiring a separate web account.