People throw around reading levels when it comes to writing: "5th grade level," "10th grade level," "college level," etc.
What concrete steps do you take to write for a specific reading level? Is there software to help with this?
The Flesch-Kincaid Grade Level Readability Formula
Step 1: Calculate the average number of words used per sentence.
Step 2: Calculate the average number of syllables per word.
Step 3: Multiply the average number of words by 0.39 and add it to the average number of syllables per word multiplied by 11.8.
Step 4: Subtract 15.59 from the result.
The specific mathematical formula is:
FKRA = (0.39 x ASL) + (11.8 x ASW) - 15.59
FKRA = Flesch-Kincaid Reading Age
ASL = Average Sentence Length (i.e., the number of words divided by the number of sentences)
ASW = Average number of Syllable per Word (i.e., the number of syllables divided by the number of words)
Analyzing the results is a simple exercise. For instance, a score of 5.0 indicates a grade-school level; i.e., a score of 9.3 means that a ninth grader would be able to read the document. This score makes it easier for teachers, parents, librarians, and others to judge the readability level of various books and texts for the students.
Theoretically, the lowest grade level score could be -3.4, but since there are no real passages that have every sentence consisting of a one-syllable word, it is a highly improbable result in practice.
A second suggestion would be to find an app to analyze your writing level, please see: http://sarahktyler.com/code/sample.php. There are many more apps available and it certainly depends upon who you are writing for and about. Workplace indicates a 10th year grade level is the best for technical writing.
Another tool for analysis is here: http://www.makeuseof.com/tag/writing-reader-friendly-check-8-readability-testing-web-tools/ You should know your audience and read a few documents that are in the document libraries, although styles may change over the years due to the natural writing style of authors.
As user8789 says, there are formulas to calculate the reading level of a sample of text. Personally, I wouldn't take these too seriously.
For example, consider this paragraph:
The children were playing with a soccer ball in the yard, and when Bethany kicked it, it went way over the fence, into the neighbor's yard, and then it rolled very far down the hill before it finally came to a stop at the river.
According to this site -- https://readability-score.com -- it's Flesch-Kinkaid grade level is 17.2. That is, it requires a post-graduate degree to understand. Do you really think that you need a PhD to understand that?
Now consider this paragraph:
The Intel CPU executes 16 million FIPS per second. It uses a high speed front-side bus to help move data between the RAM and the registers. It has a very large instruction set. This includes commands for basic adding and subtracting, indexing, and moving text data. It has a width of 64 bits.
That has a Flesch-Kinkaid grade level score of 5.2. So any 13 year old should easily be able to understand it.
The problem with these readability formulas is that they only look at lengths of words and lengths of sentences, not at the complexity of the ideas. A simple sentence like, "In my closet I found a ball, a cardboard box, three adorable dolls, a pack of baseball cars, two pairs of trousers, and a sweater" gets a fairly high grade level because there are many words in the sentence and several that are quite long. I can easily write paragraphs about computers that score very low even though they are very complex because computer people tend to use short words for very complex ideas, like "bit" and "list" and "float".
Also, these formulas only consider the number of words in the sentence, and not the complexity of the sentence structure.
George Washington was the commander-in-chief of the continental army. He was also the first president of the United States.
Grade level 7.6
George Washington was the commander-in-chief of the continental army and he was the first president of the United States.
Grade level: 11.1
That is, just joining two sentences with an "and" jumps the difficulty by 3 1/2 grade levels. In real life, I think not. Is it more difficult to read the one long sentence? I suppose. But not that much more difficult.
Before you consider that, you -- and all readers -- should look at other suggestions, many of them subtle, which are found in the books we talked about earlier.
I walked down the street and I passed the grocery store, the barber shop, the bakery, the auto mechanic, an Italian restaurant, two Laundromats, and a school with a big playground.
The second sentence scores higher because it has more words and longer words. But surely it is far easier to understand because the structure of the sentence is simple. It's just a long list.
I'm not saying the formulas are worthless. I'm just saying that I don't think they're worth very much.
If this sounds like a rant, well, maybe it is.
Read books published for that age range / reading level. This gives me a general feel for themes, characters, plot compexity etc.
Find definitions of those levels. Often publishers explain how they define the reading levels on their website for parents (who buy the books) to understand where their own child ranges. (Children's reading level varies greatly at the same age!)
Understand children and their development by observing the children I have or know and at books on developmental psychology to understand what children learn at what age: which letters can they read (if you write texts for first readers)? what vocabulary do they know? how do they look at and understand the world? etc.
I'm currently writing Young Adult, so I read a lot of YA fiction, read around for what publishers, readers, and critics say YA is (and how it relates to Middle Grade or New Adult or adult genre fiction), and read books on adolescence, visit forums frequented by adolescent users, try to remember my own experiences at that age, and observe those youths I have access to (e.g. in the bus, in courses I give etc.).