Android font size and display size are worth testing separately when your phone feels difficult to read. Changing both at once makes it harder to tell which adjustment helped and which made the layout less comfortable.
Find the two controls
Google recommends opening Settings and searching for Font size or Display size. Each setting has a slider. Use the preview while adjusting it. Menu locations vary across phones, and Google notes that some steps require Android 13 or later.
The font-size setting does not apply to every app. If one app looks unchanged, that does not necessarily mean the setting failed.
Start with text
- Note your current slider position.
- Increase font size by a small amount.
- Read a familiar message and a settings page.
- Open an app with several buttons and check that labels remain usable.
- Keep the change only if it improves your normal tasks.
Do this at your normal reading distance. A setting that looks comfortable while the phone is held very close may not solve your everyday problem.
Then test display size
Return to a familiar layout before testing the other slider. Compare how much information fits on screen and whether important controls are easier to identify. Use the same two or three apps for both trials so the comparison is meaningful.
For example, check a conversation list, a calendar, and a form with a keyboard. These expose different tradeoffs between larger content and the space available for the task.
Keep a reversible baseline
Google documents a Reset settings option in the display-size and text controls to return those preferences to the device’s original settings. Read the scope of the reset on your own phone before using it.
There is no universal best slider position. Choose the combination that lets you read comfortably and finish routine tasks without repeatedly correcting the layout.
Official reference: Read the manufacturer’s instructions.
Featured image: conceptual illustration, not a device screenshot.