Readability Calculators

Choose a tool to measure and improve the readability of your text.

Combined Readability Checker

Get all nine readability scores at once. Paste your text once and see Flesch-Kincaid, SMOG, Gunning Fog, Dale-Chall, ARI, Coleman-Liau, Linsear Write, Lix, and Rix side by side.

Flesch-Kincaid Grade Level

Calculate the Flesch-Kincaid Grade Level and Reading Ease score of your text. Ideal for general content and SEO.

SMOG Index Calculator

Measure reading grade level with the SMOG formula. Recommended for healthcare and patient-facing documents.

Gunning Fog Index Calculator

Measure reading grade level with the Gunning Fog formula. A score of 7–8 is ideal for general audiences.

Dale-Chall Readability Calculator

Measure text difficulty using the Dale-Chall familiar words list. Vocabulary-based readability for any audience.

Automated Readability Index Calculator

Measure reading grade level with the ARI formula. Uses character count—no syllable counting. Ideal for technical content.

Coleman-Liau Index Calculator

Measure reading grade level with the Coleman-Liau formula. Uses letter count per 100 words—often produces lower grade estimates than ARI.

Linsear Write Formula Calculator

Measure reading grade level with the Linsear Write formula. Developed for U.S. Air Force technical manuals. Uses easy words (≤2 syllables) vs hard words (3+ syllables).

Lix Readability Calculator

Language-neutral readability measure. Uses sentence length and long words (>6 letters). Developed by Swedish scholar Carl-Hugo Björnsson. Scores 20–60.

Rix Readability Calculator

Simplified Lix variant with grade-level output. Long words (7+ letters) per sentence. Developed by Jonathan Anderson for teachers and librarians.