A PDF, to your website, is the equivalent of getting a Bindi in your foot whilst running barefoot in the park. Its not catastrophic, like breaking your leg, but it sucks and impacts your ability to operate optimally.
Users get lost inside PDF files, which are typically big, linear text blobs that are optimized for print and unpleasant to read and navigate online. PDF is good for printing, but that's it. Don't use it for online presentation.
You should only use PDFs on on your website when absolutely necessary and applicable. For example; when users will want to download or print a document for later offline reference.
Otherwise, for day-to-day website content, you should not use PDFs. Here are some reasons why:
The content within a PDF is invisible to the web. From a search engine's perspective content within a PDF is dead, it cannot read it and therefor the content will not positively affect your Google ranking.
The PDF was built for the physical, print world, often the font size and styling is not suitable for online reading. For older visitors, users who wear glasses or are colour blind, font size, colour and contrast need to be optimised for online usage.
A usability best practice and specific WCAG standard is consistent, clear navigation. PDFs remove the user from the basic structure, navigation and flow of a website, which can be confusing and frustrating. Furthermore a PDF is a solid blob of content with no consistent way to navigate within the PDF itself.
Inappropriate use of PDFs on website is rife. Some examples of PDF usage we’ve steered our clients away from recently include; online magazines, restaurant menus and entertainment guides.
Instead we recommended moving the content from the PDFs onto actual pages, if necessary including print styling. In some cases these were basic pages, in others a particular page type required development to optimise the content for online use.
In each case there was great advantage in removing the content from the PDFs. Doing so; allowed Google to index all the content previously locked away, enabled us to optimise the content for online accessibility and to retain a consistent user friendly interface.
If you would like to know more about PDF usage online, usability or accessibility drop me an email using our contact form.