How to highlight and draw on a PDF
Mark important passages, circle details and add freehand annotations with pen and highlighter tools.
Use the pen when you want a visible freehand mark, such as a circle or underline. Use the highlighter when you want to emphasize an area without making the original information difficult to read.
Draw with the pen
- Open PDF Canvas and choose the PDF you want to annotate.
- Navigate to the relevant page and select the pen tool.
- Choose the available colour and stroke-width settings.
- Draw a short test mark before annotating a larger area. Check the result at a comfortable zoom level.
- Use the editor's available undo or selection controls if you need to correct an added mark.
Highlight an area
- Select the highlighter tool.
- Choose the colour and width offered by the editor.
- Draw across the area you want to emphasize.
- Check that the original text remains readable. Repeated strokes over the same area can make a highlight darker.
Keep annotations understandable
- Use a small, consistent set of colours.
- Keep pen strokes away from letters unless the intention is clear.
- Do not rely on colour alone if the document must also make sense in grayscale.
- Inspect several pages if your PDF contains different page sizes or orientations.
Check the downloaded PDF
Download the edited PDF under a new filename and open it in another reader. Look for misplaced marks, unexpectedly dark highlights and clipping near page edges. If you plan to print the file, inspect the print preview too.
Drawing over information is not secure redaction. Do not use a pen stroke, highlight or opaque shape as a way to permanently remove confidential information.