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Sentence Counter

Count sentences accurately with abbreviation and decimal-number detection. Get average sentence length, a Flesch readability score, and a sortable per-sentence breakdown.

Quick Answer

The Sentence Counter splits text into sentences using logic that protects common abbreviations (Mr., Ph.D., U.S.A.), decimal numbers, and domain names from being mistaken for sentence breaks. It also returns word count, average words per sentence, a sentence length distribution, a Flesch Reading Ease score, and a sortable list of every detected sentence with its word count.

Sentence Counter

Sentences0
Words0
Avg Words / Sentence0.0
Characters0
Characters (No Spaces)0
Paragraphs0
Unique Words0
Reading / Speaking Time~0m / ~0m
ReadabilityVery Confusing

Flesch Reading Ease score:

Sentence Length Mix
Short ≤10: 0Medium: 0Long: 031+: 0

Not enough sentences yet to judge variety.

Platform Limits
X / Twitter post0/280
SMS message0/160
Meta description0/160
Instagram caption0/2200

What Is the Sentence Counter?

The Sentence Counteranalyzes any block of text and returns an accurate sentence count, along with word count, average sentence length, readability score, and a per-sentence breakdown. Unlike simple tools that split on every period, this counter recognizes abbreviations (Mr., Ph.D., U.S.A.), decimal numbers (3.14), and website domains (example.com) so a single piece of text doesn't get miscounted as several fragments.

For example, "Dr. Martinez, Ph.D., published a paper on climate trends." correctly counts as one sentence here — a naive counter that splits on every period would miscount it as three.

Everything runs locally in your browser — no text is uploaded to a server, so it's safe to paste unpublished drafts, essays, or client work.

How to Use the Sentence Counter

  1. Paste or type your text into the input box.
  2. The sentence count, word count, and readability score update instantly as you type.
  3. Check the Sentence Length Mix bar to see if your writing leans too short, too long, or has good variety.
  4. Open the Sentence Breakdown list and sort by Longest first to spot run-on sentences worth splitting.
  5. Click Copy Stats to copy a plain-text summary of every metric.

Where Can You Use the Sentence Counter?

Editing and Proofreading

Spot overly long or run-on sentences instantly using the sorted sentence breakdown, instead of scanning a whole document manually.

Academic Writing

Check average sentence length and Flesch readability score against style-guide targets before submitting an essay or thesis.

SEO and Content Marketing

Most readability tools flag content with a poor sentence-length mix. Fix that here before publishing a blog post or landing page.

Social Media Copy

The Platform Limits panel shows exactly how much of the X/Twitter, SMS, or Instagram caption limit your text uses.

Metrics Explained

  • Sentences: Detected using punctuation-based splitting with protection for common abbreviations, initials, decimals, and domain names — not a naive split on every period.
  • Avg Words / Sentence: Total words divided by sentence count. 15-20 is typical for clear web writing; above 25 starts to feel dense.
  • Sentence Length Mix: Buckets every sentence into Short (≤10 words), Medium (11-20), Long (21-30), or Very Long (31+) so you can see your variety at a glance.
  • Readability (Flesch Reading Ease): A 0-100 score computed from average sentence length and syllables per word. Higher scores mean easier reading.
  • Unique Words: The count of distinct words (case-insensitive), useful for spotting repetitive vocabulary.

Best Practices and Limitations

The sentence-detection logic protects the most common false positives — titles like "Dr." and "Ph.D.", initials like "J. K. Rowling", decimal numbers, and domain names — but no punctuation-based counter is perfect for every edge case, such as dialogue with nested quotation marks or unconventional formatting. For high-stakes academic submissions, cross-check with your word processor's built-in tools.

Share This Sentence Counter

Help others discover this free, accurate sentence counter!

Frequently Asked Questions

How does this sentence counter avoid miscounting abbreviations?+

Before splitting text into sentences, the tool protects known abbreviations (Mr., Dr., Prof., etc., vs.), degree titles (Ph.D., M.D.), initials (U.S.A., J. K. Rowling), decimal numbers (3.14), and domain names (example.com) so their periods are not treated as sentence endings. A period only ends a sentence when it is followed by whitespace or the end of the text.

What is the Flesch Reading Ease score?+

It is a 0-100 readability score calculated from your average sentence length and average syllables per word. Higher scores (80-100) mean the text is easy to read; lower scores (below 50) indicate dense, harder-to-read writing typical of academic or legal text.

What counts as a "long" sentence in the length breakdown?+

Sentences are grouped as Short (10 words or fewer), Medium (11-20 words), Long (21-30 words), or Very Long (31+ words). Sentences over 30 words are also highlighted in red in the Sentence Breakdown list so you can find and split them quickly.

Can I sort the sentence breakdown list?+

Yes. Click the sort control above the list to cycle between Original order, Longest first, and Shortest first. Sorting by Longest first is the fastest way to find run-on sentences worth splitting.

Is my text uploaded anywhere when I use this tool?+

No. All counting and analysis happens locally in your browser using JavaScript. Your text is never sent to a server, which makes it safe to paste unpublished drafts, essays, or confidential documents.