What is PDF?

PDF stands for Portable Document Format which is a file format for digitally exchanging documents. The PDF format was first developed in 1993 by Adobe Systems. PDF is commonly used for two-dimensional document types that contain text, letters, images, and two-dimensional graphics.

The use of the PDF file format is recommended when you want to provide content that can be accessed offline and does not involve many changes in the content. You can use PDF files to create content in the form of ebooks, offline content, specification documents, journals, and so on.

How Google Shows PDF in Search Results

PDF was first indexed by Google in 2001. Now, more than hundreds of millions of PDF files have been indexed successfully. Google will display PDF results based on the users’ keywords. In Google search results, PDF files are marked with the PDF tag to the right of the page URL.

However, Google cannot index password-protected PDF files. Therefore, you should make sure that the content and images in PDF files are easily searchable so that search engines can crawl and index them.

PDF Optimization Tips for SEO Friendly

When you share a PDF file on their web page, you want the file to be easily detected by search engines. That way, the PDF file can reach more people. Here are tips that can be used to optimize the performance of PDF files on search engines:

Create Great Content

Create text-based content to make it easier for search engines to crawl and index your PDF files. Make sure the content have a good quality and is useful for internet users.

Optimize Title Tag

Like web pages, PDF files require titles. Search engines will match the title with the user's search query in displaying search results. You can set the title property of a PDF file via Adobe Acrobat, with the following steps:

• Click File > Properties
• Add text to the title field

Optimize Meta Description

Optimizing the meta description increase the chances of your PDF files showing up on the search results. Relevance is seen from the keywords that appear in the meta description. Here's what you can do to set the meta description property of a pdf file in Adobe Acrobat:

• Click File > Properties
• Click the Additional Metadata option
• Add text to the description field

Use SEO-Friendly File Names

Make sure the PDF file name and title match. Make sure both contain keywords and SEO Friendly. The recommended filename length is around 55-60 characters. You can use dashes or underscores to separate each word in the PDF file name.

Optimize The Image

Add alt text to make it easier for search engines to understand the image content in your PDF file. In addition, pay attention to the format and file size for optimal image performance. 

You can use vector-based images because it is relatively small-sized and good quality. You can also use monochrome bitmap images.

Create Mobile-Friendly PDF Content

Even though it has a consistent appearance on each device, you can still optimize its performance on mobile devices. Here are some tips that can be done:

• Left align text
• Add text styles such as bold, italic, underline
• Use bullets and numbering to mark important points
• Use clear and small images
• Make paragraphs short, concise, and clear

Add Link

Links in PDF files can make it easier for readers to find related information. In addition, the embedded internal or external links will affect the ranking of the PDF file in search engines. Therefore, it is important to add a link to the PDF file.

Use Canonical Tags

Search engines hate duplicate content because it complicates the indexing and ranking process. Web pages with a lot of duplicate content will have poor ranking on search engines.

As with web pages, PDF files will also be considered as plagiarism if the content is similar to other web pages. You can prevent duplicate content by using canonical tags.

Minimize PDF File Size

The size of the PDF file will affect the loading speed of the file. The smaller the size, the loading process tends to run faster.

Besides compressing files, you can also compress images, but still, pay attention to quality. The font used will also affect the file size. Therefore, make sure your PDF files use standard fonts.

Are PDFs Good for SEO?

Although Google has indexed PDF files, this file format has several reasons that make it less suitable for SEO. This is caused by the following factors:

• Not supported on mobile. PDF has the same appearance on every device, indicating that PDF is less mobile-friendly. So that the user experience on mobile devices is less optimal.
• Lack of content navigation. Most PDF files do not include navigation elements, making it difficult for people to navigate through their content.
• It lacks certain SEO elements. PDF does not have link attribute elements such as no-follow, sponsored, and UGC.
• Might be rarely crawled. Frequently updated content tends to be crawled more often than PDF content