Dreamweaver lets you increase the magnification (zoom in) in the Document window so that you can check the pixel accuracy of graphics, select small items more easily, design pages with small text, design large pages, and so on.
The user interface has been simplified in Dreamweaver CC and later. As a result, you may not find some of the options described in this article in Dreamweaver CC and later. For more information, see this article.
The zooming tools are only available in Design view.
Zoom in or out on a page
Click the spot on the page you want to magnify until you’ve achieved the desired magnification.
Drag a box over the area on the page that you want to zoom in on and release the mouse button.
Select a preset magnification level from the Zoom pop‑up menu.
Type a magnification level in the Zoom text box.
You can also zoom in without using the Zoom tool by pressing Control+= (Windows) or Command+= (Macintosh).