Sentence Length Analyzer
Analyze your text for average, shortest, and longest sentence lengths to improve readability.
How to use this tool
- Enter text in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your sentences and the full breakdown beneath it.
Analyze your text for average, shortest, and longest sentence lengths to improve readability.
How it works
Sentence length is one of the primary drivers of readability. Short sentences are punchy and easy to follow; very long sentences can lose the reader. This tool analyzes every sentence in your text and reports the average length, the shortest sentence, and the longest sentence, measured in words.
Paste your text and the tool splits it into sentences using punctuation boundaries, counts words in each, and summarizes the distribution. You can use this to identify a single runaway sentence buried in otherwise good copy, or to confirm that a piece of writing maintains good rhythmic variety.
Content writers, editors, and educators use this tool to check drafts against readability guidelines. A common recommendation is to keep average sentence length under 20 words, with occasional short sentences for emphasis and longer ones for detail.
Worked example
Analyze a product description for readability
- Paste the product description into the Text field.
- Check the average sentence length -- e.g. 28 words.
- Identify the longest sentence highlighted in the results.
- Split that sentence into two shorter ones and re-analyze.
Average sentence length reduced to 19 words; text is more scannable.
Common mistakes to avoid
- Optimizing average length while ignoring outliers -- one 60-word sentence can derail a paragraph even if the average looks fine.
- Breaking up sentences so aggressively that the text feels choppy and lacks connective flow.
- Analyzing text that includes HTML tags -- strip tags before pasting for accurate word counts.
Key terms
- Average sentence length
- The mean number of words per sentence across the entire text; a key readability indicator.
- Sentence variety
- The mix of short and long sentences in a text; variety improves rhythm and reader engagement.
Frequently asked questions
- What is the ideal sentence length?
- For readability, aim for an average of 15–20 words per sentence. Vary length to keep readers engaged — mix short punchy sentences with longer ones.
- Why does sentence length matter for SEO?
- Search engines favour readable content. Shorter sentences improve Flesch Reading Ease scores and are more accessible to a wider audience.