Sentence Counter
Count sentences and measure average sentence length for readable writing.
The Sentence Counter reports how many sentences your text contains, along with the average words per sentence and the length of your longest sentence. It is a favorite tool for writers tightening their prose and students checking assignment structure.
Average sentence length is one of the strongest readability signals: short sentences (15–20 words on average) read clearly, while 30+ word averages exhaust readers. Knowing your longest sentence lets you spot the run-on that needs splitting, and the count itself matters for style exercises, speeches and translation quotes.
Counting uses the standard rule that sentences end with a period, exclamation mark or question mark followed by a space or the end of text. The tool is instant, runs locally in your browser, and handles abbreviations imperfectly by design — it flags nothing, it simply counts.
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Sentences
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Words
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Avg words / sentence
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Longest sentence (words)
How to use the Sentence Counter
- Paste or type your text.
- Read the sentence count, total words and average words per sentence.
- Check the longest sentence's word count.
- Split long sentences in your draft and watch the average improve.
- Clear the box and check another passage.
Frequently asked questions
What counts as a sentence?
Any group of words ending in . ! or ? followed by whitespace or the end of the text. Headlines without punctuation, fragments and abbreviations like 'Dr.' or 'e.g.' can affect the count — a known limitation of every rule-based counter.
What is a good average sentence length?
For general web content, 15–20 words per sentence reads comfortably. Scientific and legal writing often runs longer; children's and marketing copy shorter. Use the tool to check where your writing actually lands.
Is this useful for readability scores?
Yes — average sentence length is one of the two core inputs of Flesch reading-ease formulas (the other is syllables per word). Sentence counters are the first step toward those readability statistics.
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