Sentence Counter
Paste or type below — counts update live. Your text stays on your device.
Sentence length is a readability lever
Average sentence length is one of the strongest signals of how a text reads. News wire copy averages roughly 15–20 words per sentence; legal and academic prose routinely doubles that, which is a large part of why it feels heavy. Trimming the average — usually by splitting the two or three longest sentences rather than shortening everything — is the fastest single edit for readability. That's why this counter surfaces the longest sentence itself, not just its length: it's the first thing worth rewriting.
One honest caveat: sentences are detected by terminal punctuation
(. ! ? followed by a space or
the end of the text), so abbreviations like "Dr." or "e.g." can
over-count slightly. For ordinary prose the estimate is reliable.
Worked example
Paste: "Short sentences carry weight. They are easy to scan. But a longer sentence, stacked with clauses and asides, slows the reader down considerably. Balance is the goal." The tool reports 4 sentences, 27 words, an average of 6.8 words per sentence, and a longest sentence of 14 words — the third one, shown in the quote box so you can see exactly which sentence is doing the slowing.
Frequently asked questions
How long should a sentence be?
There's no single right length, but the working ranges are consistent: news and web writing averages roughly 15–20 words per sentence, plain-language guidance often suggests keeping most sentences under 25, and anything past 40 words usually deserves a second look. Variety matters more than any single number — mix short and long deliberately.
Does it handle abbreviations like 'Dr.' and 'e.g.'?
Not specially — and we'd rather say so plainly. The counter treats a period followed by a space as a sentence end, so 'Dr. Smith arrived.' counts as two sentences instead of one. For ordinary prose the over-count is small; for abbreviation-heavy academic or legal text, expect the sentence count to run a little high.
What's a good average sentence length for web writing?
Around 15–20 words. Web readers scan, so shorter average sentences keep them moving; a paragraph whose average climbs past 25 usually benefits from splitting one or two long sentences. This tool shows the longest sentence too, since one 60-word monster drags the average more than several mildly long ones.
Why does dialogue-heavy text show such short sentences?
Because dialogue really is short. Spoken lines like 'Fine.' or 'Not today!' are complete sentences of one or two words, and each terminal punctuation mark ends one. A low average in fiction with lots of dialogue isn't a problem — it reflects how people talk, not weak writing.