free AI paraphraser
SI Paraphraser: same meaning, new words
A free AI paraphrasing tool that rewords sentences and paragraphs in four modes. Your meaning, your facts and your quotes stay put; only the wording changes.
Use it when you need the same meaning in new words. Click any word of the result to swap in a synonym. Not quite? Try the Humanizer, Rewriter or Summarizer.
what it does
A paraphrasing tool that respects the original
Paraphrasing sounds easy until you try it: you either stay so close to the source that nothing really changes, or you drift and the meaning shifts. The SI Paraphraser handles both sides. It changes the vocabulary and the sentence structure for real, merging or splitting sentences where that reads better, and it keeps the claims, the level of certainty and every fact exactly as they were.
It is also careful about the thesaurus trap. Swapping "big" for "gargantuan" is not paraphrasing, it is noise. The tool keeps the intensity of each word, so "unsanitary" does not quietly become "filthy".
only here
Click any word for a better one
A paraphrase is rarely perfect on the first try: one word is too formal, another repeats something you wrote above. So the SI Paraphraser lets you fine-tune the result word by word. Click or tap a word and you get 3 to 5 synonyms picked for that sentence, already in the right form and tense. One more click and it is swapped in.
Want to replace a short phrase instead? Select up to four words, then click. Keyboard users can Tab into the result, move with the arrow keys and press Enter. Synonym lookups do not use your daily words.
a real example
Standard and Simple mode, side by side
Original: "The Industrial Revolution played a crucial role in shaping modern society. It marked a significant shift from agrarian economies to industrialized ones, fundamentally transforming the way people lived and worked."
Standard mode
The Industrial Revolution reshaped modern society in important ways. It represented a major transition away from farming-based economies toward manufacturing-based systems, changing how people lived and worked at a basic level.
Simple mode
The Industrial Revolution shaped modern society in major ways. It moved economies away from farming and toward factories, which changed how people lived and worked in basic ways.
Both outputs come straight from the tool, unedited.
four modes
Pick the paraphrasing mode that fits
Standard
The everyday choice. New vocabulary, new structure, same length and same register. Good for avoiding repetition in a report, restating a point in a presentation, or writing a second version of a product description.
Fluent
For text that is correct but clunky, or written by a non-native speaker. Fluent mode fixes awkward phrasing and grammar and improves the flow between sentences, without making the language fancier.
Formal
Raises the register for cover letters, business emails, grant applications and academic work: precise vocabulary, no contractions, no slang, still readable.
Simple
Short sentences and everyday words. Useful for explaining a technical idea to customers, writing for a wide audience, or checking that you really understand a difficult paragraph.
good practice
How to paraphrase well, with or without a tool
- Understand first. Read the passage until you could explain it out loud. A paraphrase of something you do not understand is just a scramble.
- Change the structure, not only the words. Start from a different part of the idea, turn a passive sentence active, split a long sentence.
- Keep what must not change. Names, numbers, technical terms and direct quotes stay as they are.
- Check the meaning. Put the original and your version side by side. Same claim? Same certainty? Nothing added?
- Cite the source. A paraphrase of another person's idea still needs a reference.
The SI Paraphraser does steps 2 and 3 for you in a couple of seconds. Steps 1, 4 and 5 are still yours, and they are the part that makes writing honest.
use cases
What people use an AI paraphraser for
- Writing without repeating yourself. When the same point appears in the intro, the body and the conclusion, paraphrase two of them.
- Summarizing sources for notes. Paraphrase a key passage in Simple mode to check you understood it, then keep the citation next to it.
- Emails and messages. Turn a blunt first draft into Fluent or Formal wording before you hit send.
- Product and web copy. Write variants of a description for different pages without starting from zero.
- Language learners. See the same idea written two or three ways and pick up new structures.
Need more than a reword? The SI Rewriter changes tone and reworks whole articles, and the SI Humanizer strips the machine feel out of AI drafts.
SI Paraphraser FAQ
What is an SI paraphraser?
An SI paraphraser, or AI paraphrasing tool, rewrites a sentence or paragraph with new wording while keeping exactly the same meaning. It changes vocabulary and sentence structure, not the ideas.
Is the SI Paraphraser free?
Yes. You get 3 free runs a day without an account, and 3,000 words a day with a free account, shared across all tools. Each run accepts up to 1,000 words.
Can I upload a Word or PDF file?
Yes. Click "Upload a file" above the text box, or drag a file onto it: .txt, .docx (Word) and .pdf files up to 2 MB work. We extract the text, show it in the box so you can check and edit it, and delete the file right away. PDFs need selectable text: a scanned page is an image, so paste its text instead. Long files are cut at your word limit per run, with a note.
What is the difference between the four modes?
Standard rewords at the same length and register. Fluent smooths awkward phrasing and grammar. Formal raises the register for professional or academic use. Simple uses short sentences and everyday words.
Is paraphrasing the same as plagiarism?
Paraphrasing is a normal writing skill, but a paraphrase of someone else's idea still needs a citation. Changing the words does not make the idea yours. Keep the reference to your source, and check your school's or publisher's rules on AI assisted writing.
Will it keep quotes, numbers and names?
Yes. The paraphraser is told to keep proper nouns, figures, dates, quotations and technical terms exactly as they are, and to add nothing. Always read the result before using it.
How do I swap a word for a synonym?
Once the paraphrase appears, click or tap any word in the result. A small menu shows 3 to 5 synonyms chosen for that sentence, so they fit the grammar and the meaning. Pick one and it replaces the word in place. With a keyboard, Tab into the result, move with the arrow keys and press Enter. To replace a short phrase, select up to four words first.
Do synonym lookups use my daily words?
No. Synonym suggestions are free and do not count against your daily allowance. They are limited to about 60 lookups an hour to keep the service fair for everyone.
How is this different from the SI Humanizer?
The paraphraser is about saying the same thing differently. The SI Humanizer is about making machine-written text sound natural. If your text came from ChatGPT and reads stiff, start with the humanizer. If you need a new version of a sentence, use the paraphraser.
Does it work in other languages?
Yes. Paste text in French, Spanish, German, Italian or Portuguese and you get the paraphrase back in the same language.