The Best Readability Score for Blog Posts, Emails, and Landing Pages

There's a common piece of advice in content marketing circles: "Write at a 6th-grade reading level for everything." It's repeated in copywriting courses, SEO guides, and Twitter threads. It's also wrong — or at least, wrong enough that following it blindly will hurt your content.

The right readability target depends on what you're writing, who you're writing for, and what the reader is trying to accomplish. A blog post tutorial for software engineers should not be at a 6th-grade level. A landing page for a consumer mobile app should be. An email subject line has different constraints than an email body. A patient-facing medical article has legal and ethical readability requirements that don't apply to a B2B white paper.

This article gives you concrete readability targets by content type, explains the reasoning behind each, and tells you which readability formula to use for which kind of content.

The Quick Reference Table

Here's the at-a-glance version. The rest of the article explains the reasoning, the audience research, and the edge cases.

|---|---|---|---|

| Children's content (under 8) | 90–100 | 1–3 | Flesch Reading Ease |

| Children's content (8–12) | 80–90 | 4–5 | Flesch Reading Ease |

| YA fiction | 70–85 | 6–7 | Flesch-Kincaid |

| Consumer marketing copy | 70–80 | 6–7 | Flesch Reading Ease |

| Patient-facing medical content | 80–90 | 5–6 | Flesch-Kincaid (per AMA) |

| Blog post — general audience | 60–70 | 7–9 | Flesch-Kincaid |

| Blog post — B2B / technical | 50–60 | 9–11 | Flesch-Kincaid |

| Blog post — developer audience | 45–55 | 10–12 | Flesch-Kincaid (with caveats) |

| News article | 50–60 | 10–11 | Flesch-Kincaid |

| Long-form feature / opinion | 45–55 | 11–12 | Flesch-Kincaid |

| Email body (consumer) | 70–80 | 6–7 | Flesch Reading Ease |

| Email body (B2B) | 60–70 | 8–9 | Flesch-Kincaid |

| Email body (newsletter) | 60–70 | 8–9 | Flesch-Kincaid |

| Landing page (consumer) | 70–80 | 6–7 | Flesch Reading Ease |

| Landing page (B2B / SaaS) | 55–65 | 8–10 | Flesch-Kincaid |

| Sales page (long-form) | 60–70 | 8–9 | Flesch-Kincaid |

| Product description (e-commerce) | 70–80 | 6–7 | Flesch Reading Ease |

| Technical documentation | 50–60 | 9–11 | Flesch-Kincaid |

| API documentation | 45–55 | 10–12 | Flesch-Kincaid (with caveats) |

| Press release | 55–65 | 9–10 | Flesch-Kincaid |

| Resume | 55–65 | 9–10 | Flesch-Kincaid |

These ranges are calibrated against audience research, regulatory requirements, and what actually performs in each format. The reasoning for each category is below.

Why "6th Grade for Everything" Is Bad Advice

The "6th grade for everything" rule has a kernel of truth behind it. The U.S. National Assessment of Adult Literacy (NAAL), the most comprehensive study of adult literacy in the United States, found in its 2003 report that the average U.S. adult reads at roughly an 8th-grade level, with 43% of adults reading at or below "basic" literacy (defined as roughly 8th grade or below). The most recent PIAAC survey (Programme for the International Assessment of Adult Competencies, 2017) found similar numbers across OECD countries.

If you're writing for the broadest possible audience, targeting 6th–8th grade makes sense. Most public-health communication, government content, and consumer marketing follows this guideline.

But the rule breaks down in three important ways:

1. Audience varies by content type

The audience for a software engineering blog is not the same as the audience for a government public-health notice. Software engineers read at a college level by training; they expect technical vocabulary. Writing a tutorial on distributed systems at a 6th-grade level doesn't make it more accessible — it makes it harder to read, because the writer is forced to use circumlocutions for precise technical terms.

2. Genre conventions matter

A B2B white paper at a 6th-grade level signals "I don't take this topic seriously" to a sophisticated reader. A children's book at a 10th-grade level signals "I don't know my audience." Reader expectations are set by genre, and violating those expectations damages credibility regardless of whether the content is technically readable.

3. Plain language ≠ simple language

Plain language is about clarity, structure, and directness — not about vocabulary simplification. You can write at a 10th-grade level and still be perfectly clear, by using short sentences, active voice, and concrete examples. You can also write at a 6th-grade level and be perfectly unclear, by using vague abstractions and disconnected sentences. The grade level is one signal among many.

Blog Posts: The 7–9 Grade Sweet Spot

For most general-audience blog posts, the readability sweet spot is Flesch-Kincaid grade 7–9, which corresponds to Flesch Reading Ease 60–70. This is the range where:

Average sentence length runs about 12–17 words.
Average word length runs about 1.4–1.6 syllables.
Vocabulary is mostly common with occasional technical terms defined inline.

This range covers most successful general-audience publications. The New York Times front-page news runs about grade 10. The Atlantic features run about grade 11. Most successful personal blogs land between 7 and 9.

When to go lower (grade 5–7)

Consumer-facing how-to content (recipes, household tips, personal finance for beginners).
Content for audiences with known literacy challenges (patient education, ESL audiences).
Marketing copy where the goal is to be skimmed quickly.
Mobile-first content where attention spans are short.

When to go higher (grade 10–12)

B2B content where the audience has domain expertise.
Technical content where simplification would lose precision.
Opinion and long-form features where readers expect depth.
Legal and compliance content where precise language is required.

The developer-content caveat

Developer-facing content (API docs, engineering blog posts) often scores high on Flesch-Kincaid because it uses technical terms, code blocks, and precise language. A typical Stripe API doc page runs grade 12+. This isn't a problem — it's appropriate for the audience. Trying to reduce it to grade 8 by replacing "idempotency key" with "unique-token-thing" would hurt the content, not help it.

Emails: Subject Lines vs. Bodies

Email readability has two components that often get conflated: the subject line and the body. They have very different targets.

Email subject lines

Subject lines should be as simple as possible — grade 5 or below, ideally grade 3–4. Why?

Subject lines are read in a tiny mobile viewport where every word costs visual real estate.
Subject lines are processed in fractions of a second.
Pre-readers skim subject lines to decide whether to open at all.

Short, concrete, simple words win. "Your order shipped today" (grade 3) outperforms "Important Information Regarding Your Recent Purchase" (grade 11). The latter looks formal and spammy; the former looks like a real communication from a real person.

A practical test for subject lines: count the words. Aim for 5–7 words. Use words a 4th-grader would know. Avoid jargon, acronyms, and abstract nouns.

Email body — consumer

For consumer-facing emails (transactional, marketing, onboarding), target Flesch Reading Ease 70–80, which is grade 6–7. The reader is skim-reading on mobile. Short sentences, short paragraphs, concrete language. Most successful consumer emails — from companies like Amazon, Stripe, Notion — land in this range.

Email body — B2B

B2B emails can run slightly higher — grade 8–9, Flesch 60–70. The audience is professional and tolerant of slightly longer sentences and domain vocabulary. But the same principles apply: short paragraphs, clear structure, concrete calls to action.

Newsletter emails

Newsletter readability depends on the editorial voice. Morning Brew runs about grade 8. Stratechery runs about grade 12. Both work because the readability matches the brand promise. Morning Brew promises quick news in a friendly voice; Stratechery promises analytical depth. The reader expects and accepts the grade level.

The mobile constraint

Most emails are read on mobile (60–75% opens on mobile across most industries). Mobile screens reward short paragraphs (2–3 sentences max) and short sentences (15 words max). A grade-7 email with 3-sentence paragraphs reads well on mobile. A grade-7 email with 8-sentence paragraphs doesn't.

Landing Pages: The Format-Driven Readability Question

Landing page readability is unusual because the format dominates the reading experience. Most landing pages have:

A headline (5–10 words).
A subheadline (15–25 words).
Bullet points (5–15 words each).
A short body section (1–2 paragraphs).
A call to action (2–5 words).

The Flesch-Kincaid score of a landing page is dominated by the headline and bullets, which are typically short and concrete. Most successful landing pages score grade 6–8 overall.

Consumer landing pages

Target grade 6–7 (Flesch 70–80). The reader is deciding whether to sign up for something. Clarity and brevity win. Example pages: most B2C mobile apps, consumer SaaS like Calm or Headspace, e-commerce product pages.

B2B / SaaS landing pages

Target grade 8–10 (Flesch 55–65). The reader is evaluating a tool for a specific use case. They expect more detail, including feature lists, integration lists, and technical specs. Example pages: Stripe, Datadog, Linear, Vercel landing pages.

Long-form sales pages

Long-form sales pages (used in info-product marketing, course launches, and high-ticket coaching) typically run grade 8–9. They use longer paragraphs than landing pages but still use short sentences and concrete language. The challenge with long-form sales pages isn't grade level — it's structure. A grade-7 page with poor structure will fail; a grade-9 page with strong structure will convert.

Pricing pages

Pricing pages are a special case. They're not really "writing" — they're tabular content. Readability formulas produce odd numbers on tables. Focus on clarity and consistency instead. Use the same vocabulary across tiers. Define every column. Don't hide the "Most Popular" tier behind scroll.

Patient-Facing Medical Content: A Legal and Ethical Constraint

Patient-facing medical content has stricter readability requirements than almost any other category. The American Medical Association (AMA) recommends patient education materials be written at a 5th–6th grade reading level. The National Institutes of Health (NIH) recommend 6th–8th grade. The U.S. National Institutes of Health's Clear Communication program treats 8th grade as the maximum.

These recommendations aren't just best practices — they're tied to patient safety. Studies have consistently shown that patients who don't understand their discharge instructions, medication labels, or treatment plans have worse health outcomes. The AMA estimates that low health literacy costs the U.S. healthcare system $100–$238 billion annually.

If you're writing patient-facing content, target Flesch-Kincaid grade 5–6 (Flesch 80+). Use short sentences, define every medical term, and avoid Latin abbreviations where possible.

Government Content: The Plain Writing Act

The U.S. Plain Writing Act of 2010 requires federal agencies to write public-facing documents in "clear Government communication that the public can understand and use." The operational guidance is Flesch Reading Ease of 60 or higher, or Flesch-Kincaid grade 8 or lower. Federal agencies are required to use plain language in:

Documents needed to obtain federal benefits or services.
Documents for filing taxes.
Documents explaining how to comply with federal requirements.
Letters about federal benefits or services.

Many state governments have similar requirements. The UK government has its own plain-language standard, GOV.UK style, which targets a reading age of 9 (roughly grade 4–5).

Technical Documentation: The Tradeoff

Technical documentation is where readability guidance gets most contested. On one hand, technical docs are often read by non-native English speakers and by stressed users trying to solve a problem. On the other hand, technical docs use precise terminology that resists simplification.

The practical answer: target grade 9–11 for general technical documentation, with structured simplification. That is, use precise technical vocabulary (don't say "the unique-token-thing" when you mean "idempotency key"), but use short sentences, define terms on first use, and provide glossary links.

API documentation often runs grade 10–12 because of the density of technical terms. This is appropriate; the audience is developers who expect precision. Trying to simplify an API reference to grade 6 would damage its usability.

Which Formula to Use When

Five readability formulas are commonly available in tools. Each has strengths:

| Formula | Best for | Notes |

|---|---|---|

| Flesch Reading Ease | General content; comparing texts | 0–100 scale; higher = easier |

| Flesch-Kincaid Grade Level | Mapping to U.S. school grades | Most widely used grade-level score |

| Gunning Fog Index | Business and academic content | Weights "complex words" (3+ syllables) heavily; over-penalizes jargon |

| SMOG (Simple Measure of Gobbledygook) | Health and patient content | More accurate on shorter samples (30+ sentences); validates well against comprehension tests |

| Coleman-Liau | Web content (uses character counts, not syllables) | More accurate when syllable counting is unreliable (e.g., for languages other than English) |

For most general-purpose content, Flesch-Kincaid is the default — it's the one most tools compute, the one most stakeholders recognize, and the one with the clearest grade-level mapping.

For health and patient content, SMOG is preferred by many health literacy researchers because it predicts comprehension difficulty more accurately on shorter passages.

For B2B and academic content, Gunning Fog is sometimes preferred because it explicitly weights complex words, which is a useful signal in formal writing.

For web content where syllable counting is unreliable (e.g., when the content contains code snippets or unusual proper nouns), Coleman-Liau — which is based on character counts rather than syllable counts — is more reliable.

How to Use These Targets Without Becoming Obsessive

The biggest risk with readability targets is optimizing blindly. A few practical guidelines:

Use the target as a band, not a number. If your target is grade 7–9 and your draft comes back at grade 8, you're done. Don't keep tweaking to hit exactly grade 7.5. The band is what matters.

Diagnose, don't just measure. If your draft comes back at grade 12 when you wanted grade 8, look at what's driving the score. Long sentences? Replace Latinate words with Germanic ones. Long words? Cut nominalizations. The score tells you something's off; your analysis tells you what.

Trust your reader-testing over the formula. If real readers from your target audience say your content is clear, the formula's number doesn't matter. If real readers say your content is confusing, the formula's number also doesn't matter. The formula is a proxy for real-reader comprehension, not a substitute for it.

Differentiate the score from the structure. A grade-7 page with no headings, walls of text, and no visuals is harder to read than a grade-10 page with clear headings, short paragraphs, and helpful visuals. Structure and formatting affect readability more than grade level.

Watch for false signals. A page with many code blocks will score artificially high. A page with many lists will score artificially low. A page with many proper nouns (company names, product names) will score in ways that have nothing to do with readability. Adjust your interpretation accordingly.

A Workflow for Hitting Your Target

If you're building a content workflow around readability, here's what works:

Set the target upfront. When you start a piece, decide on the target grade band based on the audience and content type. Write it down.
Write the first draft without checking the score. Let your natural voice come through. Optimization comes later.
Run the draft through a readability tool. If you're in the target band, move on. If you're outside, identify what's driving the score.
Revise with specific techniques. Shorten sentences. Cut filler. Replace Latinate words with Germanic. Use active voice. Cut nominalizations.
Re-test. If you're still outside the band, repeat.
Do a final human read. The score is a check, not the final word. If the draft reads well to a human, ship it. If it doesn't, the score is irrelevant.

The Bottom Line

The best readability score for your content depends on what you're writing and for whom. There's no universal target. There's only the right target for your specific piece, your specific audience, and your specific context.

The table at the top of this article gives you starting points for the most common content types. Use them as a calibration, not a constraint. For most web content aimed at general adult audiences, Flesch-Kincaid grade 7–9 is the safe band. For consumer marketing and patient-facing content, drop to grade 5–7. For B2B, technical, and academic content, accept grade 10+ as appropriate.

The readability score is a diagnostic, not the goal. The goal is content your reader can understand, use, and remember. Our readability analyzer runs Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog, and SMOG on your text in real time — use it as you draft, so you can adjust sentence length and word choice before the draft is finished.