Free Reading Level Checker — Flesch-Kincaid, SMOG & More

Analyze the readability of any text using five industry-standard formulas. Paste content, upload a document, or fetch any URL. See word counts, long sentence highlights, and complex word detection. Free, no signup.

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Reading Level Checker — Write for Your Audience

The average American reads at a 7th–8th grade level. Most web content is written at a 10th grade level or higher. This gap costs you readers, conversions, and credibility.

Paste your content, upload a document, or fetch any URL to instantly measure reading difficulty across five industry-standard formulas.

Flesch Reading Ease

72.4Standard

Flesch-Kincaid

8.28th grade

Gunning Fog

10.1Moderate

SMOG Index

9.49th grade

Dale-Chall

6.8Standard

The Five Readability Formulas

Flesch Reading Ease

0–100 (higher = easier)

The most widely used readability formula. Developed by Rudolf Flesch in 1948. Scores above 60 are considered accessible for most adults. Used by the US Department of Defense for its documents.

Flesch-Kincaid Grade Level

US school grade equivalent

Uses the same variables as Flesch Reading Ease but outputs a US grade level instead. A score of 8 means the text is appropriate for an 8th-grade student. Developed for the US Navy in 1975.

Gunning Fog Index

Grade level (target: below 12)

Developed by Robert Gunning in 1952 to measure how much education a reader needs to understand a text on first reading. Penalises both long sentences and complex words (3+ syllables).

SMOG Index

Grade level (most accurate with 30+ sentences)

Simple Measure of Gobbledygook. Developed by Harry McLaughlin in 1969. Widely used in healthcare and public health writing. Research suggests it is the most accurate formula for predicting comprehension.

Dale-Chall Score

Score mapped to grade range

Instead of counting syllables, Dale-Chall uses a list of ~3,000 words familiar to most 4th-grade students. Words outside the list are 'difficult'. Developed by Edgar Dale and Jeanne Chall, revised 1995.

Target Reading Levels by Content Type

Children's content

Grade: 3rd–5th gradeFRE: 80–100

General web content / blogs

Grade: 6th–8th gradeFRE: 60–80

News articles

Grade: 8th–10th gradeFRE: 50–70

Business / marketing copy

Grade: 8th gradeFRE: 60–70

Technical documentation

Grade: 10th–12th gradeFRE: 40–60

Healthcare / patient info

Grade: 6th grade or belowFRE: 60+

Legal / academic

Grade: College+FRE: 0–40

How to Improve Your Reading Level Score

Shorten your sentences

Aim for an average of 15–20 words per sentence. Break long sentences at natural conjunctions.

Replace complex words

Use the annotated view to find 3+ syllable words. Replace 'utilise' with 'use', 'demonstrate' with 'show', 'approximately' with 'about'.

Use active voice

Active voice is shorter and easier to parse. 'The team completed the project' vs 'The project was completed by the team'.

Break up paragraphs

Shorter paragraphs feel easier to read even when word complexity is the same. Three to five sentences per paragraph is a good target.

Use the Dale-Chall list as a guide

If a word isn't in the familiar words list, consider whether there's a simpler alternative. Not all complex words can be replaced — technical writing has necessary vocabulary.

Frequently Asked Questions

Which readability formula should I trust most?

No single formula is definitively best. Use Flesch Reading Ease for a quick overview, Flesch-Kincaid for US grade level context, SMOG for healthcare content (it is the most validated for comprehension prediction), and Dale-Chall when vocabulary difficulty is your main concern. The consensus across formulas gives you the most reliable picture.

Why do my scores differ across formulas?

Each formula weighs different variables differently. Flesch focuses on sentence length and syllable count. Gunning Fog counts complex words differently from SMOG. Dale-Chall doesn't count syllables at all. It is normal to see variation, especially on shorter texts.

How accurate is the syllable counter?

The rule-based syllable counter is accurate for the vast majority of common English words. It may over- or under-count syllables in unusual proper nouns, technical terms, or non-English words. For research-grade accuracy, manual verification of edge cases is recommended.

Is my text stored or sent to a server?

Text pasted directly into the tool is analyzed entirely in your browser — no server involved. The URL fetch feature sends only the target URL to a server-side proxy (to avoid CORS restrictions), not your text.

What is a good reading level for blog content?

Aim for a Flesch Reading Ease score of 60–70 and a Flesch-Kincaid grade level of 7th–8th grade. This is accessible to most adult readers without feeling dumbed down. Major publications like Time and the BBC write at roughly this level.