PDF Markup Tools

PDF Markup Tools

When viewing a PDF in CoLab, you can use the markup tools found at the top left of your screen. Add markups to PDFs using CoLab's markup tools. Save your markups as feedback and assign the feedback to another CoLab user. You can also communicate about the feedback in real-time, with all history tracked under the feedback. For details on how to leave and assign feedback in CoLab, see Adding Feedback in a PDF.

As you hover over each option on the toolbar, the name of the viewer appears.  Pro Top: Double click on any markup tool to make it the dominant markup tool in use. Here’s how each tool works:

Box Select - You can select single markup by clicking on an object or click and drag on the canvas to select multiple objects. Once an object or multiple objects are selected you can click and drag those objects around the canvas. If a single object is selected, you can click on the anchors located on the corner of the object.

Pen - Allows you to make pen-like markups on the PDF. Click on the ‘Pen’ button to expand the toolbar with Stroke Color and Stroke Width options to change the color of the stroke or its width. Double click on the ‘Pen’ button to make it the dominant markup tool in use. 

Highlight - Allows you to make highlights on the PDF. Click on the ‘Highlight’ button to expand the toolbar with the Stroke Color button to change the color of the stroke. Double click on the ‘Highlight’ button to make it the dominant markup tool in use. 

Markup Shapes - Allow you to select a desired shape that is used to highlight an area and leave feedback on it.  Click on the ‘Markup Shapes’ button to expand the toolbar with options to change the Fill Color, Shape Color and Stroke Width. 

Line - Allows you to draw lines on the PDF. Click on the ‘Line’ button and use the Stroke Color and Stroke Width buttons to modify the line. Double click on the ‘Line’ button to make it the dominant markup tool in use. 


Arrow - Allows you to draw arrows on the PDF. Click on the ‘Arrow’ button and use the Stroke Color and Stroke Width buttons to modify the shape. Double click on the ‘Arrow’ button to make it the dominant markup tool in use. 


Callout - Creates an arrow, associated text box and feedback window. Click on the ‘Callout’ button to expand the toolbar with options to change the shape fill, line color, text color, shape line width and font size. Double click on the ‘Callout’ button to make it the dominant markup tool in use. 

Text - Allows you to place text boxes on the PDF. Click on the ‘Text’ button and use the toolbar options to change the text color or size. 


Undo/Redo - Allow you to undo or redo any of the activities from this toolbar. 


Delete - Allows you to delete any activities from this toolbar. WARNING: deleted activities cannot be recovered.