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Sentence Splitter Text

Break a paragraph into one sentence per line — for subtitles, translation, or reading it back critically.

Sentence Splitter is a free online tool that break a paragraph into one sentence per line — for subtitles, translation, or reading it back critically. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.

Price
Free — no account, no quota, no watermark
Category
Text
Where it runs
In your browser, on your device
Files uploaded
None
Technology
plain JavaScript
Settings
3
Works offline
Yes, after the first visit

About Sentence Splitter

Splitting on a period is wrong, and the reasons are worth listing because they are the same ones every naive implementation trips over: abbreviations (Dr., Inc., e.g.), decimals (3.14), initials (J. R. R.), ellipses, and domain names. The rules here protect each of those before splitting and restore them afterward. It will still be wrong occasionally — the complete solution requires understanding the words — but it handles ordinary prose correctly.

How to use it

  1. Paste the text you want to run through sentence splitter.
  2. Set number each sentence, blank line between sentences and merge fragments shorter than.

The 3 settings

SettingWhat it doesDefault
Number each sentenceOn or off. Off by default.Off
Blank line between sentencesOn or off. Off by default.Off
Merge fragments shorter thanRange 1–10 words.2 words

Under the hood

Runs onplain JavaScript — runs the whole thing
ControlsNumber each sentence, Blank line between sentences, Merge fragments shorter than

Questions

Why did it split in the wrong place?

Probably an abbreviation not on the list. The common ones are covered — titles, months, business suffixes, Latin abbreviations — but the long tail is endless. Raising the merge threshold reattaches short fragments, which fixes most of the remainder.

What is the fragment merge setting?

A piece shorter than the threshold is almost always a missed abbreviation rather than a real sentence, so it is joined back to the one before it. Two words is a sensible default; raise it if your text is full of unusual abbreviations.

What is one sentence per line good for?

Subtitles and captions, translation memory, and reading your own writing critically — a wall of prose hides a run-on sentence, and a list of them makes it obvious. Some technical writers draft this way permanently, because it gives clean line-by-line diffs.