Total Character Count, Total Word Count and Readability should all be considered as interactive measures. Character count and Word Count are fairly obvious but readability may be less so.
Readability estimates the age of the reader required to read and understand the content. Changing the reading age of the content may include making some of the words longer or shorter and this will impact on character count.
The readability measure is basically teh number of years of education it is required to easily understand teh written content.
Don’t get bogged down with the literal translation of this. They are simply numbers that reflect teh readability. These numbers are used as comparisons in ESS so as long as teh calculations that get the numbers are consistent the teh comparison is relevant. In other words we are measuring apples with apples.
In practice the number is derived from a number of different “industry standard” measurement of readability and combined together to give an estimated “reading age”
In practice sentence length can have a big impact of the readability but the length and complexity of the words are also important.
Many sources suggest that the average web page can be read by a nine year old so it seems that simplicity is generally the key here. However you need to temper that with the target audience. It is unlikely that the same readability is required for a scientific report as for a post about children’s toys.
Also it is important to note that Readability measure does not cover spelling mistakes and poor grammar however this is good opportunity to address both.
Content quality is currently very high on Google’s radar so remember that a low reading age does not mean writing rubbish. All content should be relevant, interesting, useful and unique.
So review these three measures together. Consider the overall affect of your changes on these measures to make sure that what you do keeps all three in line with the top 10 results.