The PDF you need to email is 30 MB, but the email service only accepts attachments up to 10 MB. Or a document management system won’t let you upload anything larger than 5 MB. The most common cause of such a large PDF is scanned pages or photos. In this article: how to reduce the size of a PDF file without making the text illegible.
Why is the PDF file so large?
- Scans at too high a resolution. A 600 dpi colour scan takes up several times more space than a 300 dpi one, even though 300 dpi is perfectly adequate for text.
- Photos from a phone. Each shot is several megabytes, and ten such pages already add up to a large file.
- Embedded fonts and unnecessary data – in PDFs created by desktop publishing software.
How to reduce a PDF with ABBYY FineReader PDF
- Open the PDF file in the FineReader PDF editor.
- Choose the reduce file size function.
- Specify how much to compress the images: 300 dpi is usually enough for text documents, and even less will do for on-screen viewing.
- Save the file under a new name and compare it with the original to check that the text is still easy to read.
If the document is scanned, it’s worth recognising it too (OCR): the file not only gets smaller, but you can also search its text. We described how this works in our article what is OCR.
How to avoid large files in the first place
- Scan text documents at 300 dpi – a higher resolution only makes the file bigger.
- For black-and-white documents, choose greyscale rather than full colour.
- Don’t photograph a document in several shots if you can scan it.
Are free online tools any good?
For an unimportant file – yes. However, online PDF compressors upload the document to someone else’s server, often limit file size and compress it so heavily that small print becomes illegible. For contracts, invoices and documents containing personal data, it’s better to use software that processes the file on your own computer.
Which FineReader edition to choose
To reduce PDF files, edit them and recognise text, ABBYY FineReader PDF Standard (Windows) is enough. If you need to combine files into one, read our article how to merge PDF files. For larger volumes and automated processing there is the Corporate edition, and for Mac computers – FineReader PDF for Mac. All the differences are in the comparison table.