How To Increase Your Flesch-Kincaid Grade Level (Step-by-Step Guide)

Most writing advice tells you to make your content simpler. Shorten sentences. Trade long words for short ones. Drop your reading level so an eighth-grader can follow along. But sometimes you need to do the opposite.

If you write for an academic journal, a technical white paper, a legal brief, or a professional audience that expects sophisticated prose, you may need to raise your Flesch-Kincaid Grade Level rather than lower it.

This guide explains exactly how to increase your Flesch-Kincaid Grade Level, how the formula actually works, how it relates to your Flesch Reading Ease score, and, just as importantly, when raising your readability score is the right call and when it will quietly hurt your content.

What Is the Flesch-Kincaid Grade Level?

The Flesch-Kincaid Grade Level is a readability formula that estimates the U.S. school grade level a reader needs to understand a piece of text.

A score of 8.0 means the average eighth-grader can follow the writing. A score of 12.0 means it reads at a high-school-senior level, and a score of 16.0 or higher signals college-graduate or professional-level complexity.

The formula was developed for the U.S. Navy in the 1970s to assess the difficulty of technical manuals, and it has since become one of the most widely used readability metrics in publishing, education, and content marketing.

It is built directly into tools most writers already use, including Microsoft Word, Google Docs add-ons, Grammarly, Hemingway, and Yoast SEO.

Here is the actual equation:

FKGL = 0.39 × (total words ÷ total sentences) + 11.8 × (total syllables ÷ total words) − 15.59

Strip away the constants and you are left with two things that matter:

1. Average sentence length — words divided by sentences
2. Average word length — syllables divided by words

Everything you do to raise your grade level comes down to increasing one or both of those numbers.

Flesch-Kincaid Grade Level vs. Flesch Reading Ease

People often confuse these two scores because they come from the same family of readability formulas, but they run in opposite directions.

The Flesch Reading Ease score rates text on a 0-100 scale, where higher numbers mean easier reading. Its formula is:

Flesch Reading Ease = 206.835 - 1.015 × (words ÷ sentences) - 84.6 × (syllables ÷ words)

Here is how the two relate: when your Flesch Reading Ease score goes down, your Flesch-Kincaid Grade Level goes up. They are essentially two views of the same underlying data. So if your goal is to increase your grade level, you are also, by definition, lowering your Reading Ease score.

For reference, here is roughly how Flesch Reading Ease bands map to grade level:

To increase your Flesch-Kincaid Grade Level, you are aiming to push your writing down this table, from "plain English" toward "difficult" or "very difficult."

When Should You Increase Your Grade Level?

Before the tactics, a word of caution. For most web content, blog posts, and marketing copy, a lower grade level performs better.

Easier text keeps readers on the page longer, converts more effectively, and is friendlier to mobile skimmers. Deliberately raising your readability score can backfire if your audience just wants a quick answer.

That said, there are legitimate reasons to increase your Flesch-Kincaid Grade Level:

• Academic writing. Journals, dissertations, and research papers are expected to read at a college-graduate level.
• Technical and scientific documentation. Precise terminology naturally raises the score, and simplifying it can introduce inaccuracy.
• Legal, financial, and regulatory content. Certain documents require exact, formal language.
• Professional and B2B audiences. Executives, specialists, and expert readers may perceive overly simple writing as lightweight or condescending.
• Meeting an institutional requirement. Some assignments, style guides, or rubrics specify a minimum reading level.
• Matching a sophisticated brand voice. A luxury, academic, or authority-driven brand may want prose that signals expertise.

If one of those describes your situation, the following techniques will reliably move the number.

How to Increase Your Flesch-Kincaid Grade Level

Because the formula rewards longer sentences and longer words, every technique below targets one of those two levers.

1. Lengthen Your Sentences

Average sentence length is the single most controllable input. Short, punchy sentences drop your grade level; longer, layered ones raise it.

• Combine short sentences. Two seven-word sentences become one fourteen-word sentence, and the average sentence length climbs.
• Add subordinate clauses. Use words like although, because, whereas, since, and while to attach dependent clauses that extend the sentence without breaking it.
• Use coordinating conjunctions to join ideas. Link related independent clauses with and, but, yet, and however rather than ending the sentence early.
• Introduce parenthetical and appositive phrases. Insert clarifying detail mid-sentence, set off by commas or dashes, to add length and complexity.

The trade-off is real: excessively long sentences hurt comprehension. The goal is controlled elaboration, not run-ons.

2. Choose Multisyllabic Vocabulary

The second lever is syllables per word. Because the formula weights syllable count heavily, swapping short words for longer synonyms raises your grade level quickly.

• use → utilize
• help → facilitate
• show → demonstrate
• start → initiate
• end → terminate
• buy → purchase
• enough → sufficient
• build → construct

Domain-appropriate terminology does the same work more naturally. In a technical or academic context, precise multisyllabic terms both elevate the score and improve accuracy, which is the ideal combination.

3. Use Complex Sentence Structures

Beyond raw length, structural complexity signals a higher reading level. Favor complex and compound-complex sentences over a string of simple ones.

Nest clauses, use relative pronouns (which, that, whose), and vary your syntax so sentences carry multiple layers of meaning.

4. Incorporate Nominalizations

Nominalization, which is turning verbs and adjectives into nouns, is a hallmark of formal, academic prose and reliably raises grade level.

Decide becomes decision, analyze becomes analysis, implement becomes implementation. These noun forms are typically longer and encourage denser, more abstract sentence construction.

5. Reduce Reliance on Short Function Words

Text heavy with short, one-syllable words (is, the, a, to, go, get) reads at a low grade level. Where accuracy allows, replace weak verbs and generic phrasing with more precise, longer alternatives. Get better becomes improve; go up becomes increase; a lot of becomes numerous or substantial.

6. Add Technical Detail and Qualification

Precise, qualified writing tends to score higher because it uses more words and more specialized vocabulary.

Adding conditions, caveats, and specificity ("under most operating conditions" rather than "usually") naturally extends sentences and raises the reading level while making the content more rigorous.

Tools to Measure Your Readability Score

You cannot manage what you do not measure. Check your Flesch-Kincaid Grade Level and Flesch Reading Ease with any of these readability tools:

• Microsoft Word — enable "Show readability statistics" in the spelling and grammar settings, and Word displays both scores after each check.
• Hemingway Editor — highlights long and complex sentences and reports an overall grade level.
• Grammarly — shows a readability score and reading level in its performance panel.
• Yoast SEO — flags Flesch Reading Ease directly inside WordPress, useful for web publishing.
• Readable.com and similar readability checkers — provide detailed breakdowns across multiple readability formulas at once.

Measure a baseline, apply the techniques above, then re-check. Because the formula is transparent, you will see exactly which changes moved the number.

Common Mistakes to Avoid

Raising your grade level is easy to overdo. Watch for these pitfalls:

• Sacrificing clarity for complexity. A high readability score means nothing if readers cannot follow the argument. Complexity should serve meaning, not obscure it.
• Padding with filler. Adding empty words to inflate sentence length is transparent and weakens your writing.
• Ignoring your audience. Match the reading level to who is actually reading. A technical audience welcomes density; a general audience does not.
• Overusing jargon. Specialized terms raise the score, but jargon for its own sake alienates readers and signals insecurity rather than expertise.
• Forgetting SEO context. If this content lives on the web and needs to rank and convert, an artificially high grade level can increase bounce rate. Balance the requirement against real reader behavior.

Related Tools and Guides

These free tools and guides pair well with this article:

• Free sentence rewriter: rewrite a sentence three different ways.
• Free paragraph expander: develop a thin paragraph.
• Free grammar checker: fix grammar and see what changed.
• Read our guide to humanizing AI content: practical edits that work.
• Read our beginner's guide to copywriting: a step-by-step roadmap.

Last Words About the Score

Increasing your Flesch-Kincaid Grade Level comes down to two dials: longer sentences and longer words.

Combine short sentences, add subordinate clauses, choose multisyllabic vocabulary, use nominalizations, and layer in precise technical detail, then measure the result with a readability tool and adjust.

But raising the number is not automatically an improvement. The best writers do not chase a high or low readability score, but instead calibrate their reading level to the people they are writing for.

Use these techniques when your audience, format, or requirements genuinely call for sophisticated prose, and resist them when plain, direct language would serve your readers better.