The following instructions work for all Kindles, with specific callouts where there are different steps for specific models.
You cancheck to see which Kindle you haveif you aren’t sure.
If your Kindle doesnt have a touchscreen, skip this step.

On Kindle 1-3, push the physicalAa button.
On Kindle 4, push themenuicon, then selectChange Font Size.
In the Size section, tap-to reduce font size and+to increase font size.

When youre done, tap in the top part of the screen to return to your book.
Why Cant I Change the Font Size on My Kindle?
This option isnt available on the home screen, in the library, or in the unit options.

If you obtain an ebook from another source, you may not be able to change the font size.
This issue can also crop up when you load documents like PDFs directly onto your Kindle.
If youconvert the PDF to Kindle format, youll be able to adjust the text size.

If that doesn’t work either, contact Amazon for additional support.
FAQ
Connect your Kindle to your gear and drag the font files into theFontsfolder.
New fonts will show up when you tap theAaicon.

In the Kindle app, tap the center of the screen and tapAato bring up font options.
In theKindle app for PC, selectAanear the top of the app window.
From here, you’ve got the option to change fonts and adjust the text size.