There are two different methods with which you can annotate a PDF doc with Diigo.

(If you don’t want to read the tutorial,  try the PDF annotation feature directly.)

Mehtod 1:   Annotate a PDF doc by first uploading it  to the Diigo website

• Step 1:  Upload a pdf doc to your diigo library in “My Library” page;
• Step 2: Open the uploaded PDF doc in your browser, and you should see a toolbar on top of the doc;
• Step 3: Select text to highlight or add a sticky note. Your highlight and sticky notes on the PDF will be saved in your Diigo library.

Method 2: Annotate a PDF using the  Diigo browser extension (available for Chrome and Firefox only, and the instructions below are for Chrome)

• Step 1: Open an online PDF doc,within Chrome, with the Diigo extension installed;
• Step 2: Click the  “Annotate” button at the upper right corner of the opened PDF doc (see the first screenshot below). The doc is then opened again with a toolbar on top (see the second screenshot below);
• Step 3: Select text to highlight or add a sticky note. Your highlight and sticky notes on the PDF will be saved in your Diigo library.

How to Annotate and Clip non-text PDF Doc

If a PDF doc is in a form of an image, then you cannot highlight any text, but you can use the screenshot feature of of the Diigo extension (chrome and firefox) to capture or crop the image, and then annotate it as a screenshot.

Export an annotated PDF doc

The annotated PDF doc can be exported.  However, due to some tech limitation, after being exported, in-line sticky notes are invisible  for mac users who use preview as their pdf reader.

Due to the complexity of the PDF format and the compatibility issues for different browsers and browser versions,  Diigo PDF annotation may not work perfectly for every PDF file. If you experience any issue,  please do let us know.