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Troubleshooting

How to Translate a PDF

Translate a document while keeping it readable — the options, what happens to the layout, and the privacy question nobody asks.

August 9, 20262 min read

Translating a PDF is two problems: translating the words, and putting them back on a page where the text is now a different length.

Translate a document

  1. 1Open the Translate PDF tool and add your file.
  2. 2Choose the source and target languages.
  3. 3Translate, and read the result before relying on it.

The layout problem

German runs roughly 30% longer than English; Chinese is considerably shorter. Text that fitted its box no longer does, or leaves a gap. Because a PDF has fixed positions rather than flowing paragraphs, there is no reflow to absorb the difference — something has to overflow, shrink or be truncated.

That is why translated PDFs so often look slightly wrong. It is a property of the format, not a failure of the translation.

What machine translation is good and bad at

ContentQuality
Everyday prose between major languagesVery good
Technical documentationGood, with terminology drift
Legal textRisky — terms of art rarely map cleanly
Medical textRisky, and consequential
Marketing copyLiteral; the tone does not survive
Tables of figuresThe numbers survive; the headings may not

When it needs a human

Anything with legal effect, anything where a mistranslation carries safety consequences, and anything being published under your name. Machine translation is excellent for understanding a document you received; it is not a substitute for a professional translator on a document you are issuing.

Getting a better result

  • OCR scans first — there is nothing to translate in an image.
  • Translate section by section for a long document, so you can check as you go.
  • Keep the original alongside the translation, and say which is authoritative.
  • Have a native speaker review anything published.
  • For a document you control, translate the source and re-export rather than translating the PDF.

That last point is the real answer whenever it is available. Translating the Word file and exporting again gives you a properly laid out document instead of a patched one.

Do it now

Translate PDF

Translate PDF content to any language. It runs in this browser tab — your file is not uploaded anywhere.

Open Translate PDF

Frequently asked questions

Does translation preserve the layout?+

Approximately. Text length changes and PDF positions are fixed, so overflow and gaps are normal.

Is my document sent to a server?+

Yes — machine translation runs remotely. Consider that before translating confidential material.

Can I translate a scanned PDF?+

Run OCR first, then translate. Recognition errors will propagate into the translation.

Is machine translation good enough for contracts?+

For understanding one, often. For issuing one, no — use a professional translator.

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