iPhone tower · floor

How to make text bigger on iPhone, everywhere or in one app

There are three answers to how to make text bigger on iPhone, and they are genuinely different: a normal size, a much larger range, and a slider that changes the size only in the app you happen to be using. Apple documents all three in different places.

Two screens, and the second one goes further

Apple documents both, on two different pages. They lead to sliders with different ranges.

The ordinary size
Settings → Display & BrightnessText Size, then drag the slider. From Apple’s support article on font size, dated August 2023.
The larger range
Settings → AccessibilityDisplay & Text SizeLarger Text, then drag the slider. And for more than that: turn on Larger Accessibility Sizes. The current iPhone User Guide documents this route.

Those two routes end in the same place — a slider — but the second one reaches further, and Larger Accessibility Sizes extends it again. If the slider has been dragged to its end and the text is still too small, that switch is the thing that extends it.

“Change the size of text while you’re in an app. Open Control Centre, then adjust the Text Size slider. If you don’t see the Text Size slider, tap in the top-left corner, tap Add a Control, then tap the Text Size control.”

Apple files this as a tip, and it is the most useful thing on the subject. The setting screens change the text everywhere at once; this changes it where you are standing. Larger type in a reading app and ordinary type everywhere else is a real arrangement, reachable from wherever you already are. The catch is in Apple’s second sentence: the slider is not on the panel until you add it, so on most phones it is not there to be found.

It is worth spelling out what that changes about the whole question. Text size stops being one decision for the entire phone and becomes something you set per situation: bigger for reading, ordinary for everything else, adjusted in the moment rather than in Settings. For anybody who wants large text only sometimes, that is the arrangement they were looking for.

Why some apps ignore all of this. Apple’s wording is precise and easy to read past: the size applies to “all supported apps”, and elsewhere to apps “that support Dynamic Type”. The examples Apple gives are its own — Calendar, Mail, Messages, Notes, Settings, Contacts, Phone.

So an app whose text stays stubbornly small is not necessarily misbehaving and is not a setting you have missed. It is an app that has not adopted the feature. Apple does not publish a list of which third-party apps have, and this floor is not going to guess at one.

Three neighbouring settings on the same screen

Of those three, Display Zoom is the one worth knowing about first if the difficulty is not only with words. Enlarging text leaves the buttons the same size; Display Zoom enlarges the interface with it, which is a different kind of help and a different setting.

Making the text too large might make it hard to tap buttons or other functions within apps. Go back to your settings and adjust the font size as needed.”

Apple’s own caution, and a fair one. Text and layout share the same screen: past a certain size something has to give, and what gives is usually a button being pushed off the edge or squeezed into an unreachable strip. If a phone becomes hard to operate right after this change, that is the first thing to undo — and the fact that Apple warns about it in advance means it is a known trade rather than a fault.

One more route Apple points at rather than describes here, and it is worth knowing exists: visual accessibility settings can be customised for specific apps. So between the Control Centre slider and the per-app settings, “bigger text” does not have to be an all-or-nothing choice about the whole phone — which is the assumption most of the frustration around this setting starts from.

The floors below take it three ways: the two settings screens, the per-app slider, and the neighbouring settings for when size alone is not the problem.

Where to start

Three ways in.

“The slider does not go far enough.”
Start at the two screens
“I want it bigger only in one app.”
Go to the control centre slider
“One app ignores the setting.”
That is dynamic type

The two screens

Display and Brightness for the ordinary range, Accessibility for the larger one — and a further switch that extends it again. Guides that name one are describing half of it.

The Control Centre slider

A control that changes text size inside the app you are in — and that is not on the screen until you add it, which is why it goes unfound.

Dynamic Type

The setting only reaches apps that support it. Apple names its own; for everybody else’s, it publishes no list and this floor does not invent one.

What this tower will not do

It will not tell you there is one text size setting. Apple documents two screens with different ranges, and a third control that works inside a single app.

It will not blame an app that ignores the setting. Dynamic Type is something an app has to support, and Apple publishes no list of which third-party ones do.

And it will not skip Apple’s warning. Text large enough can make buttons hard to reach, and Apple says so before you drag the slider rather than after. What holds instead is simple: the two routes to text size, the Larger Accessibility Sizes switch, the Control Centre Text Size slider and how to add it, the note that the setting applies to apps supporting Dynamic Type, the Bold Text, Display Zoom and Show Borders settings and the warning about text that is too large are quoted from Apple’s own documentation, listed below.

Where this page got its facts

  1. Apple, iPhone User Guide — Make text easier to read on iPhone (that a single preferred text size can be set for all supported apps including Calendar, Mail, Messages, Notes and Settings; the Settings → Accessibility → Display & Text Size → Larger Text route and the Larger Accessibility Sizes switch; the Bold Text option described as making text heavier; the tip to change text size while in an app using the Control Centre Text Size slider, and how to add that control if it is not shown; that Display Zoom increases the size of text as well as interface elements like icons and buttons; and the Show Borders setting for controls, buttons and Control Centre) — support.apple.com, read 22 August 2026.
  2. Apple, Change the font size on your iPhone, iPad, and iPod touch — published 22 August 2023 (that font size can be changed in Mail, Contacts, Calendar, Phone, Notes and other apps that support Dynamic Type; the Settings → Display & Brightness → Text Size route; the Settings → Accessibility → Display & Text Size → Larger Text route for larger options; and the warning that making the text too large might make it hard to tap buttons or other functions within apps) — support.apple.com, read 22 August 2026.

Written by Alberto Gulotta

Founder and editor of AI Tools Primer, writing from Palermo, Italy. Thirty-five years of taking computers apart, starting with a Commodore 64 — the long version is on the about page.

Something wrong on this page? Write to aitoolsprimer@gmail.com and it gets fixed.

Written on 22 August 2026.

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