The magnifier enlarges the question on the screen. It does not change the graph's axes inside Desmos. It is one of the tools in digital ACT tools.
When to use it
Use it for a dense figure, a small exponent, or a passage line you keep misreading. Zoom in, read the detail, then zoom back out so you can see the whole item and the choices. It is not a timing tool, and it does not pause the section.
The highlighter and the line reader keep your place. They do not enlarge anything. Those are in the highlighter and line reader.
Desmos zoom is a different control
If a graph is off the coordinate window, zoom inside Desmos. That is not this magnifier. The graphing version is in zooming off-screen graphs. Crossing out choices while the text is enlarged is in the answer eliminator.
The bottom line
Magnify the item when the print is the problem. Zoom the Desmos axes when the graph itself is missing.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
This article offers general ACT prep guidance. The ACT can change from year to year, including its format, scoring, policies, test dates, and fees, so always confirm the latest details on the official ACT website at act.org before you make decisions. ACT® is a registered trademark of ACT, Inc. thirty-six is not affiliated with, endorsed by, or sponsored by ACT.