Blog readers skim. Anything above Grade 10 lowers time-on-page and bumps bounce rate. Content sites consistently rank better when readability sits at Grade 7-9 — short sentences, common words, varied rhythm.
Aim for Flesch-Kincaid Grade 7-9 (Flesch Reading Ease 60-70). HubSpot, Medium's top performers, and most popular Substack newsletters cluster around Grade 8. Anything above Grade 12 reads as academic — fine for niche technical blogs, too dense for general audiences.
Not directly via a "readability penalty." But Google measures dwell time, scroll depth, and bounce rate as ranking signals. Hard-to-read content correlates strongly with all three negative signals. Improving readability typically improves rankings as a downstream effect.
No. Hemingway-style ultra-short sentences also bore readers. The goal is varied rhythm. Grade 7-9 with sentence-length variance (some 5-word sentences, some 25-word) reads best. Grade 4 with all 6-word sentences feels childish.
AI tends to produce consistent Grade 12-16 prose — long sentences, polished structure, multi-syllabic vocabulary. That's exactly the opposite of what blog readers want. After paraphrasing or rewriting AI text, re-check readability — it should drop into the 7-9 band.
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