Sentence Counter

Sentence length is the most reliable readability signal there is, and the easiest to act on. Nearly every plain-English guideline lands in the same place: prose that averages 15 to 20 words a sentence reads comfortably, and writing that consistently runs past 25 starts losing readers regardless of how good the ideas are.

This counter gives you the average alongside the longest and shortest sentence, and counts how many run over 25 words. Those outliers are usually where the problem is — a single 60-word sentence buried in an otherwise readable page does more damage than a slightly high average across the whole thing.

Counting sentences properly is harder than splitting on full stops. Abbreviations like Dr. and e.g., decimal numbers such as 3.14, and ellipses all contain full stops that do not end a sentence, and a naive counter inflates the total on any real piece of writing. Those cases are handled here, so the number matches what a person would count.

Treat the verdict as a signal rather than a rule. Technical documentation and legal writing legitimately run longer than a landing page, and a deliberate long sentence followed by a short one is a stylistic device rather than a mistake. The figure is most useful when it surprises you.

Everything is calculated in the page, so nothing you paste is sent anywhere.