By Jim Karpen on Fri, 04/14/2017
Reader Mode in Safari is a great way to reduce the clutter on a web page in order to make it easier to read. When you enable Reader Mode, Safari strips away all the ads and sidebars and other extraneous material and just shows you the article itself with accompanying images. This feature becomes even more useful if text size is an issue for you when reading. You can adjust the text size in Reader Mode to a size that makes it easy for you to read. Here’s how to change text size for Reader Mode on iPhone.
Related: How to Customize Safari Reader Mode
How to Change Text Size for Reader Mode on iPhone
Open Safari on iPhone.
Near the top of the page, turn on Reader Mode by tapping on the icon with parallel lines that appears just to the left of the menu bar when you're looking at a page.
To make the text larger or smaller, tap on icon at the top left that shows two upper-case ‘A’s of different sizes.
Tap the large A to make the text larger in Reader Mode.
Tap the small A to make the text smaller.
You can also change the background color and text font from this small menu in Reader Mode. But Reader Mode isn't available for all web pages, so sometimes you won't see the Reader Mode icon when viewing a web page in Safari.