W
WParaphraser.io vs Undetectable AI
Pricing, features, platforms and who each one suits — side by side.
P
Choose Paraphraser.io if…
- you want the lower entry price ($3.96/mo vs $5/mo)
- you're in its core audience: students, content writers
U
Choose Undetectable AI if…
- you work on Chrome
- you're in its core audience: students, content writers and marketers
Side by side
Feature Paraphraser.io Undetectable AI
Pricing modelFreemiumFreemium
Starting price$3.96/mo$5/mo
Free plan
Free trial
API
Open source
Tone/style modes—
Humanize AI text—
Summarizer—
Frozen words—
Non-English languages—
File import/export—
PlatformsWeb, APIWeb, Chrome, API
CategoryParaphrasing & RewritingAI Humanizers
Company—Undetectable Inc.
Full feature lists
P Paraphraser.io
- 10+ paraphrasing modes, including Academic, Formal and Humanize
- Custom tone mode
- Click-to-swap synonym suggestions
- Frozen words to protect key terms
- Text extraction from images and screenshots
- Speech-to-text and recorded audio input
- File upload
- Support for 20+ languages
U Undetectable AI
- Sentence-level AI content detection
- AI humanizer that rewrites text to read naturally
- Paraphrasing tool and AI essay writer
- AI plagiarism checker and text watermark remover
- Image, audio, video and deepfake detectors
- Fake PDF, receipt and ID detectors
- Chrome extension for Google Docs and Gmail
- Supports 50+ languages
Their home pages
What each vendor shows first: the pitch, the plans and the sign-up.
Paraphraser.io · paraphraser.io
Undetectable AI · undetectable.aiWhat you'd pay
The cheapest plan that fits, per month, billed yearly where the plan offers it.
Work it out for your team
- Paraphraser.ioDiamond$3.96/mo
- Undetectable AI10K words$5/mo
The cheapest paid plan with a published price that fits. Custom and sales-quoted plans aren't included.
What the free plans include
Paraphraser.io
- Word limit shown as 0 / 400 words in the input box
- Word changer, fluency, standard, formal & smooth modes with 600 words limit
- Other modes (Creative, Smarter, Shorten, Academic, Expand) shown as premium-gated
- Pro raises the limit to 1500 words
Undetectable AI
Free plan limits aren't published.
All plans and prices
Paraphraser.io
FreeFree
Silver$4.55/week
Gold$9.55/month
Diamond$0.99/week, billed annually at $47.52
Undetectable AI
10K words$9.99/mo, or $5.00/mo billed yearly ($60)
20K words$19.00/mo, or $9.50/mo billed yearly ($114)
35K words$31.00/mo, or $15.75/mo billed yearly ($189)
50K words$42.50/mo, or $21.25/mo billed yearly
BusinessCustom
Price changes we've recorded
We re-read each pricing page every month and log what changed.
Paraphraser.io
No changes since we started tracking.
Undetectable AI
- Nov 8, 2026Pricing model: Free trial → Freemium; 10K words: $5 → $9.99; 20K words: $9.50 → $19; 35K words: $15.75 → $31; 50K words: $21.25 → $42.50
Strengths and limitations
Paraphraser.io
- Free tier with five modes and no daily cap
- Supports more than 20 languages
- Accepts image, audio and file input
- Annual Diamond plan works out to about $3.96 per month
- API access only on the Diamond plan
- Advanced modes such as Creative and Academic require a paid plan
- Paid plans cap the total words and paraphrases
Undetectable AI
- Detection and humanizing in one tool
- Unlimited AI detecting on all individual plans
- Yearly billing roughly halves the monthly price
- Chrome extension works in Google Docs and Gmail
- Free trial is limited to 250 words
- Accuracy is highest in English
- Humanizing is capped by the plan's monthly word limit
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Facts from each vendor's public pages, prices checked Oct 26, 2026. Editorial policy