[android] What is the default text size on Android?

I have a mixture of Buttons and an own View, where I set my text size using Paint.setTextSize(). I want the text size to look the same like the text on the Button. Now, I can of course set the text size of the button to e.g. 18sp, and use 18 in my view. But for a better integration, I simply would like to know, what text size is "normal" for buttons. From my test, it should be something like 12sp, but I have not found any documentation on this.

Leaving the default sizes leaves way too small text on the view.

Maybe I should use still another approach to this issue?

Looks like someone else found it: What are the default font characteristics in Android ?

There someone discovered the default text size, for TextViews (which use TextAppearance.Small) it's 14sp.

In general:

Three "default" textSize values:

 - 14sp
 - 18sp
 - 22sp

These values are defined within the following TextAppearances:

 - TextAppearance.Small
 - TextAppearance.Medium
 - TextAppearance.Large

More information about Typography can be found in the design guidelines

Related to your question:

If you don't set a custom textSize or textAppearance, TextAppearance.Small will be used.

Update: Material design:

New guidelines related to font and typefaces. The standard rule of 14sp remains (body).

Examples how to set textappearances

AppCompat version:

android:textAppearance="@style/TextAppearance.AppCompat.Body"

Lollipop and up version:

android:textAppearance="@android:style/TextAppearance.Material.Body"

the default text size of the textview

if you not used any of the below

TextAppearance.Small

TextAppearance.Medium

TextAppearance.Large

then the default size is 14sp

Default values in appcompat-v7

<dimen name="abc_text_size_body_1_material">14sp</dimen>
<dimen name="abc_text_size_body_2_material">14sp</dimen>
<dimen name="abc_text_size_button_material">14sp</dimen>
<dimen name="abc_text_size_caption_material">12sp</dimen>
<dimen name="abc_text_size_display_1_material">34sp</dimen>
<dimen name="abc_text_size_display_2_material">45sp</dimen>
<dimen name="abc_text_size_display_3_material">56sp</dimen>
<dimen name="abc_text_size_display_4_material">112sp</dimen>
<dimen name="abc_text_size_headline_material">24sp</dimen>
<dimen name="abc_text_size_large_material">22sp</dimen>
<dimen name="abc_text_size_medium_material">18sp</dimen>
<dimen name="abc_text_size_menu_material">16sp</dimen>
<dimen name="abc_text_size_small_material">14sp</dimen>
<dimen name="abc_text_size_subhead_material">16sp</dimen>
<dimen name="abc_text_size_subtitle_material_toolbar">16dp</dimen>
<dimen name="abc_text_size_title_material">20sp</dimen>
<dimen name="abc_text_size_title_material_toolbar">20dp</dimen>

Default text size vary from device to devices

Type Dimension Micro 12 sp Small 14 sp Medium 18 sp Large 22 sp

http://petrnohejl.github.io/Android-Cheatsheet-For-Graphic-Designers/

Text size

Type    Dimension
Micro   12 sp
Small   14 sp
Medium  18 sp
Large   22 sp

You can find standard sizes for everything in Google's style guide.

Here are the values they use for for buttons:

Buttons

English: Medium 14sp, all caps

Dense: Medium 15sp, all caps

Tall: Bold 15sp