> For the complete documentation index, see [llms.txt](https://docs.sevenpens.com/drawtab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sevenpens.com/drawtab/core/active-area/active-area-size.md).
# Active area size
## Introduction
Because the active area is rectangular, we can describe its size in different ways.
* Width & Height
* Diagonal length
* Area
Most often, we describe active area size by its **diagonal length**.
If you need help picking the right size for your tablet, see [Choosing the right size for a drawing tablet](/drawtab/buying/choosing-size.md).
## Size in tablet names
You can often see the diagonal length in the names of pen displays. For example:
* Wacom Cintiq Pro **27**
* Huion Kamvas Pro **16** Plus 4K
For pen tablets, manufacturers often use descriptive names such as "small" and "large" instead of numbers.
* Wacom Intuos Pro Medium
* Wacom Intuos Pro Large
## Standard sizes
By looking at Wacom's product line and naming, we can build a useful framework for how descriptive words like "small" and "large" map to numbers. Note that the size names differ between pen displays and pen tablets.
## Distribution of active area sizes
If we look at how drawing tablet models are distributed along this scale, we can see a lot of variation.
## Diagonal vs Area
Is it reasonable to use the active area's diagonal length instead of its area?
I think it is, because diagonal length correlates reasonably well with area for drawing tablets.
Let's compare them by plotting the values for 180 different tablets.
For pen tablets:
And for pen displays:
Overall, I think using the diagonal is reasonable.