Paste an email. See its Flesch reading ease, grade level, and sentence-length distribution. No AI, just math.
People read marketing email at roughly 250 words a minute, in a skim pattern that resembles an F-shape: first line, opening of each paragraph, last line, CTA. Anything that slows the skim hurts conversion.
We compute two standard readability metrics. Flesch Reading Ease is a 0–100 score where higher is easier (aim for 60+ for general audiences). Flesch-Kincaid Grade Level tells you the US school grade required to parse the text — most great emails hit between grade 5 and 8.
We also chart sentence-length distribution. The pattern that correlates with high engagement is bursty: short sentences (under 8 words) interleaved with the occasional longer one. If your histogram is dominated by 16-25 word sentences, you're putting the reader through cognitive load they didn't sign up for.
This tool runs entirely server-side with no AI — math you can trust, in milliseconds. Free as long as you want to use it.
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