How to shrink/split large PDF to less than 50 MB

Question

I have a large tech PDF. It's 2500 pages with images and 100 MB in size. I'd like to try and read it on my Kindle. To my understanding, PDFs have to be less than 50 MB in order to read on the Kindle.

I downloaded PDFSAM, but if it splits the PDF into multiple PDFs by the number of pages, the file size doesn't seem to shrink more than 5 MB (so 95MB). I even tried breaking the PDF down every 100 pages.

It has a feature that will split by file size, but it doesn't seem to do anything to this PDF.

Is there a free way that I can get it down to less than 50 MB? I don't know if I can lower the quality of the PDF to make it smaller (might not be drastic enough though), split it up into multiple ones less than 50 MB, or even strip the images out of it.

I tried Calibre, which converted the file to a MOBI format. However, the MOBI file was about 200MB, and Gmail wouldn't accept it as an email attachment.

Solution 1

You could delete all images from a copy of the PDF, via a few lines of either: Java, C#, or VB.Net, alternatively you could use the PDF->Mobi conversion tool in Calibre, as this can reduce image quality to suit a kindle.

Solution 2

PDF Scissors was developed to take the hassle out of PDF reading on Kindles. It may be beneficial to you.

http://www.pdfscissors.com/

Comments

[Hoppe]

I just tried PDF scissors. It was helpful to remove the margins, but for some reason the PDF actually got 5 MB bigger :(

[Hoppe]

The Aspose library is $800 for a single license. Calibre didn't reduce the file size when it converted it to Mobi... It made it bigger.

[Hoppe]

thank you for the suggestions. Ironically the limit on Sedja.com is 50 MB as well

[Simon]

@Hoppe I hope something turns up, if I find out more I will let you know

[arober11]

What options did you set for the Calibre conversion e.g. ebook-convert --no-images someFile.pdf someFile.mobi Also note: Aspose offers a 30 day trial, while the pdfbox libraries and Calibre App are FREE.