This website uses "HTML 2 PDF Rocket". It's a great service that allows you to convert HTML urls, files, or direct code to a saved PDF file.

Full disclosure: I am receiving a 50% credit by mentioning them, but I use their service continually. Their pricing is quite affordable, and their free tier (what I'm using) offers up to 200 PDF conversions a month.

If you have HTML to PDF conversion needs, you should check them out: www.html2pdfrocket.com