<pre>
pdfcrop --margins '-4 -4 -4 -5' --clip input.pdf output.pdf
</pre>

<p>
calibre is a powerful and easy to use e-book manager. Users say it’s outstanding and a must-have. It’ll allow you to do nearly everything and it takes things a step beyond normal e-book software. It’s also completely free and open source and great for both casual users and computer experts. 
</p>
<p>
PDFCrop is a Perl script that crops the white margins of PDF pages and rescales them to fit a standard size sheet of paper. It makes the printed pages far more attractive to read! 
</p>
<h3>Links</h3>
<ul>
<li><a href="https://calibre-ebook.com/">https://calibre-ebook.com/</a></li>
<li><a href="https://pdfcrop.sourceforge.net/">https://pdfcrop.sourceforge.net/</a></li>
</ul>