Compress PDF is the one to use when a file is too large to email or upload to a portal. It recompresses only the photos inside the PDF and leaves text and vector graphics untouched, so text stays selectable. Choose Low, Recommended or Extreme, or type a target size and it lowers quality step by step until the file fits. There are ready-made pages for common limits, from Compress PDF to 100 KB up to Compress PDF to 10 MB. Scanned and photo-heavy PDFs shrink the most; a PDF that is only text and fonts can barely be reduced, and if the result isn't smaller, you get the original back with a note that it is already optimized.
Repair PDF helps when a file won't open or shows errors. It first rewrites the file structure to recover damaged reference tables and broken objects, then tries reloading and saving it again. As a last resort it rebuilds the pages as images, which look the same but lose selectable text, and it tells you when that happens. It can't recover content that is no longer in the file.
OCR PDF recognizes text in scanned documents in English, Spanish or Portuguese. It adds an invisible text layer over each page, so the PDF looks exactly the same but you can search, select and copy the text. Pages that already have text are skipped by default. The first time, the language data downloads from ConvertirDocs (several MB); your document is never sent. Accuracy depends on how sharp and well lit the scan is.
Every tool in this group shows you what it did. Compress PDF displays the size before, after and the percentage saved, and accepts several PDFs at once, downloading them as a ZIP. OCR PDF shows a progress bar page by page, since recognizing text takes longer on long documents. Repair PDF tells you which method worked, so you know whether the text is still selectable.
A common order is Scan to PDF, then OCR PDF, then Compress PDF. OCR is also the step to run before PDF to Word, PDF to Excel or PDF to TXT on a scanned file, because those need real text.