The Question Everyone Asks: Can GPT Replace Translation Tools?
Honest answer: for reading comprehension — yes. For document delivery — no.
This is not a knock on GPT. I tested GPT-4o Vision on a 10-page product spec. The results were a mixed bag.
What GPT Actually Does Well
Narrative text translation quality is genuinely good. Grammar is natural, context understanding is strong, long sentences handled better than most MT engines.
But the output format is the problem. GPT always gives you plain text. No table formatting, no multi-column layout, no bilingual comparison, none of the original PDF visual structure.
The Counterargument: GPT-4o Vision Reads PDF Layout!
This feature exists. But my test results were disappointing. Using GPT-4o Vision to translate a two-column academic paper — output looked formatted, but tables were misaligned, two columns collapsed to one, and reference numbering was scrambled.
Worse: this kind of error looks correct.
Why "Looks Right" Is More Dangerous Than "Clearly Wrong"
OCR failure is obvious. "Conversion failed" — you know to fix it. But GPT-4o Vision output looks professional. Paragraphs flow, formatting "works." You might not notice column three of a table shifted left by two cells.
The Recommendation: Complement, Not Replace
Use GPT to read and understand PDFs. Use PDFTranslate for document output. These are not competitors — they are a workflow.