Two kinds of PDF
There are text-based PDFs (created from Word, Google Docs, or a browser) and scanned PDFs (photos of pages). Text-based PDFs convert to Word cleanly because the text is real, selectable data. Scanned PDFs are images, so they need OCR to recognise the letters first — and the result is less reliable.
How to convert
Open a PDF-to-Word tool, upload the PDF, and download the .docx. For a text-based PDF you will get editable paragraphs, headings, and most of the layout. Open it in Word or Google Docs and fix any spacing the conversion did not get exactly right.
Why the layout sometimes shifts
PDF describes exact positions on a page; Word describes a flowing document. Converting between the two means guessing where paragraphs, columns, and tables belong. Simple documents convert almost perfectly; complex multi-column or heavily designed pages may need cleanup.
Getting the cleanest result
Start from the original text-based PDF if you have it (not a scan or a print-to-PDF of a photo). After converting, check tables and columns first — those are where conversions struggle. For a scanned document, expect to proofread the recognised text.
The reverse: Word to PDF
Going the other way — Word to PDF — is always clean, because you are fixing a flowing document into exact positions. Use that when you want to share a final, unchangeable version that looks the same on every device.