Readability Score Analyzer — Free Online
Last updated: March 16, 2026
A readability analyzer calculates reading level scores using Flesch-Kincaid, Gunning Fog, SMOG, and other formulas. Paste your text below to check its readability grade level instantly.
Check readability with Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, ARI & Dale-Chall. Instant grade level & sentence analysis. Free — no signup.
Content creators, SEO professionals, students, and editors who need to analyze text metrics and readability.
100% free, runs entirely in your browser — no signup, no data sent to any server.
How to Use the Readability Analyzer Tool
Readability Analyzer Features and Options
About the Free Online Readability Analyzer
How to Check Readability Online
1. Paste your text. Copy at least 30 words into the input area. Longer texts (200+ words) produce more accurate readability scores.
2. Review the scores. See your average grade level and Flesch Reading Ease at a glance, then explore individual formula scores in the card grid.
3. Compare to benchmarks. Use the comparison panel to see how your text compares to Harry Potter, The New York Times, and academic journals.
4. Find difficult sentences. Click "Show Sentence Analysis" to see which specific sentences push your grade level higher, so you can simplify them.
Why Readability Scores Matter
Readability determines whether your audience actually reads and understands your content. Studies consistently show that simpler writing reaches more people, increases engagement, and improves comprehension. The average American adult reads at an 8th-grade level, which is why the U.S. government, healthcare organizations, and major publications all target this level.
Content marketing and SEO. Google has repeatedly emphasized that content should be written for users first. Pages with clearer, more readable content tend to have lower bounce rates and higher engagement metrics. While readability is not a direct ranking factor, its effects on user behavior signals are well documented.
Healthcare and legal communication. The SMOG formula was specifically designed for health literacy assessment. The CDC, NIH, and many hospitals require patient materials to be written at a 6th-grade level. Legal plain language initiatives also push for lower grade levels to ensure contracts and notices are understandable.
Academic and technical writing. While academic writing naturally scores at higher grade levels, awareness of readability helps researchers communicate findings more effectively. Many journals now encourage authors to include plain-language summaries alongside technical abstracts.
The most actionable readability improvement is sentence length. Long, compound sentences with multiple clauses are the primary driver of high grade levels. Breaking long sentences into two shorter ones almost always improves readability without losing meaning.
Frequently Asked Questions About Readability Analyzer
What is the Flesch Reading Ease score?
The Flesch Reading Ease score rates text on a 0–100 scale, where higher scores mean easier reading. Scores of 60–70 are considered standard for general audiences. Scores above 80 are very easy (suitable for 6th graders), while scores below 30 indicate very difficult academic or technical writing.
What grade level should I target?
For general audiences, target grade 8 (the level recommended by most plain language guidelines). Blog posts and marketing copy work best at grades 6–8. Business communication typically falls at grades 8–10. Academic writing may range from grade 12 to 16+.
What is the Gunning Fog Index?
The Gunning Fog Index estimates the years of formal education needed to understand text on first reading. It weighs sentence length and the percentage of complex words (three or more syllables). A fog index of 12 means roughly college-level reading. Most popular writing targets a fog index of 8–10.
How is the SMOG Index different?
SMOG (Simple Measure of Gobbledygook) focuses specifically on polysyllabic words (3+ syllables) and is considered one of the most accurate readability formulas for health-related content. It was designed to predict the grade level a reader needs to comprehend text fully, making it the standard for medical and public health communications.
What does the Dale-Chall score mean?
The Dale-Chall formula compares words against a list of 3,000 words that most 4th-grade students know. The more 'difficult' words (not on the list), the higher the score. Scores below 5.0 are easily understood by 4th graders. Scores of 9.0+ are college-level. It is particularly useful for assessing readability for younger or less experienced readers.
Why do the different formulas give different grades?
Each formula weighs different factors. Flesch-Kincaid focuses on sentence length and syllable count. Coleman-Liau uses character count instead of syllables. SMOG emphasizes polysyllabic words. Dale-Chall uses a familiar word list. The average across all formulas gives the most balanced estimate.
What do the sentence colors mean?
When you enable sentence analysis, each sentence is colored by its individual grade level. Uncolored sentences are grade 8 or below (easy). Yellow sentences are grade 9–12 (moderate). Red sentences are grade 13+ (difficult). This helps you identify specific sentences that could be simplified.
Is my text sent to a server?
No. All readability calculations happen entirely in your browser. Your text is never transmitted, stored, or logged.
Related Free Online Tools
Check readability here, then explore our other writing analysis tools.