It depends.
The time needed to recognize text from your file depends on the following:
- Amount of selected languages (more is slower)
- Amount of selected pages (more is slower)
- Quality of your source image (better quality - quicker recognition)
Approximately, typical scanned A4 document took 10 seconds to recognize, but scanned books in PDF format, that contain 100+ pages may take 10+ minutes to recognize.
Unfortunately, we don't have conversion progress for our OCR tools yet, so if you believe that your file is reasonably small and the amount of time it's been recognized is unreasonably big - read the article about File conversion stuck on 'Converting' stage and restart your conversion.