Sentence editing tool
Sentence Length Checker
Find long sentences, check average sentence length, and improve readability for essays, articles, emails, and web copy.
- Free
- No Signup
- Private Browser-Based Tool
- Works on Mobile
Private browser-based tool
Sentence Length Checker
Find long sentences, check average sentence length, and improve readability for essays, articles, emails, and web copy.
What is a sentence length checker?
A sentence length checker measures average sentence length and flags long sentences that may be hard to read. It helps writers improve clarity, pacing, readability, and paragraph structure without changing the meaning of the text.
Who is this tool best for?
Best for editors, students, copywriters, SEO writers, UX writers, and business teams improving clarity.
- Find sentences over 25 words
- Check average sentence length
- Improve readability scores
- Edit dense paragraphs
- Review landing page copy
- Make emails easier to read
Simple workflow
How to Use Sentence Length Checker
Paste or type text
Add your draft, article, essay, caption, email, script, or document to the text box.
Review instant results
Check the live stats, warnings, table, or formatted output without refreshing the page.
Edit for clarity
Use the signals to shorten, format, clean, or improve the text for real readers.
Copy or download
Copy the final text or download a TXT file when you are ready.
Quick reference
Sentence Length Guide
Use these ranges as practical editing guides. Exact requirements can vary by school, publisher, platform, or client.
| Use | Guide |
|---|---|
| 1-10 words | Very short and punchy |
| 11-20 words | Clear for most web writing |
| 21-25 words | Usually acceptable |
| 26+ words | Review for possible trimming |
Works for English Writing Worldwide
SentencesCounter is built for English writing used in the United States, United Kingdom, Canada, Australia, New Zealand, Ireland, South Africa, and international English-language teams that publish in English.
Privacy-First Browser Processing
The tool runs in your browser. It does not require signup and does not upload your pasted draft by the counter. This is useful for essays, emails, business documents, scripts, and unpublished website copy.
Helpful answers
Frequently Asked Questions
What is a good sentence length?
For general writing, 15 to 20 words per sentence is often clear. Use variety, but avoid too many long sentences.
Does the tool find long sentences?
Yes. It lists sentences over 25 words in the long sentence detector.
Can long sentences hurt readability?
Yes. Too many long sentences can make text harder to scan and understand.
Can I use it for SEO content?
Yes. It helps make landing pages, blog posts, and articles easier to read.
Does it rewrite sentences?
No. It gives measurements and warnings so you can edit the text yourself.
Is the text private?
Yes. The check runs in your browser.
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