How to Tell Whether Your Writing Is Actually Readable

You can run a readability score and still not know whether a reader will understand what you wrote. The useful question is not “what grade level is this?” It is “can the people I am writing for find the point, trust it, and know what to do next?”

That is a different test. A grade-level formula can notice sentence length, word length, and a few surface patterns. It cannot know your audience, your purpose, whether the important fact is buried, or whether the next step is obvious. Readability is audience fit plus structure plus plain wording plus sentence-level friction.

The CDC Clear Communication Index is a good corrective because it treats readability as a material people have to use. The Index says it provides research-based criteria for developing and assessing public communication products, and its user guide says the 20 items build on plain language techniques. The first lesson is practical: before you polish sentences, decide what the piece is for.

Start with one main message. If a reader could only remember one sentence, what should it be? Put that message near the top, not after the background. If there is an action the reader should take, say it plainly. “Save this receipt before you close the claim” is more readable than three paragraphs implying the same thing.

Then check audience fit. Digital.gov’s plain language guide puts the rule simply: write for your audience. It also warns against the common myth that plain language means “dumbing down” everything for everyone. A note for tax lawyers, a reminder for parents, and a label inside an app can all be readable at different levels. The question is whether the chosen reader already knows the terms you use, has enough context, and can tell which details matter.

Structure does much of the work. Headings should tell the reader where they are, not decorate the page. Long blocks need chunks. Lists help when the reader must compare steps, requirements, or exceptions. The CDC’s core Index items include whether the material uses bulleted or numbered lists, whether it is organized in chunks with headings, and whether the most important information is summarized in the first paragraph or section. Those are not cosmetic checks. They are how a busy reader decides whether to keep going.

After that, look at wording. Prefer common words your audience uses. Use active voice when it makes responsibility clearer. “The clinic will call you” tells more than “you will be contacted.” Replace filler before you replace specialized terms. Sometimes the technical word is the right word; the problem is usually the unexplained technical word, not precision itself.

Only then should you use sentence-level scores. They are useful as smoke alarms. If a paragraph has many long sentences, nested clauses, passive constructions, and abstract nouns, a score may catch the drag before a human reviewer does. But the score should send you back to the reader’s task. Shortening every sentence can produce choppy writing that is easier to count and harder to follow.

A practical review pass looks like this:

Name the intended reader and what they need to do after reading.
Mark the main message. If you cannot find it, write it.
Move the main message to the top.
Add headings where the reader’s question changes.
Turn dense steps or conditions into a list.
Replace vague words with concrete ones.
Split only the sentences that slow down meaning.
Ask someone in the target audience what they think the piece tells them to do.

That last step matters. The CDC’s “How to Use the Index” page says the Index can assess clarity before release, support discussion between writers and reviewers, and quickly assess already released material. It also recommends testing materials with the primary audience to confirm they understand and can use the material as intended. A score cannot substitute for that.

Shadowfetch publishes Proselens for this second-draft moment: not to declare writing “good,” but to point at hard sentences, passive phrasing, filler, complex words, and readability estimates so the writer can decide what to revise. It is our app, so treat that as a disclosure, not independent proof. The judgement still belongs to the audience and the purpose.

If you want one durable rule, use this: readable writing is not writing that looks simple to a formula; it is writing that gives the right reader the right handle at the right time.