GPTinf is a web-based writing toolkit that detects, humanizes, paraphrases, and proofreads AI-assisted text for students, educators, and content professionals.
About
GPTinf is an online writing toolkit built around a central problem: text produced by AI models often carries stylistic patterns that AI detectors flag, and writers need a way to check, revise, and clean up drafts before submitting or publishing them. The platform bundles six tools in one place so a user can move from detection to revision to final checks without switching services.
At a high level, GPTinf works in a check-fix-submit flow. A writer pastes text into the AI detector to see how it scores, runs the humanizer to rephrase machine-sounding passages, then uses the plagiarism, readability, and grammar checkers to finish the draft. The humanizer offers eight writing modes and lets users lock specific terms so key vocabulary survives the rewrite. Free tiers require no registration, and the company states that submitted text is not stored, shared, or used for training after a session ends. Payments run through Paddle.
Key Features
Pricing & Fees
- Pricing: Paid plans start at $4.99/month (Lite, 5,000 humanizer words), $12.49/month (Pro, 25,000 humanizer words), and $29.99/month (Unlimited, no word limits). Annual billing is advertised at 50% savings.
- Free tier: All tools offer a free tier with no account required; free humanizing shows a preview of the result before payment.
- No storage of submitted text: The vendor states text is not stored, shared, or used for model training after the session ends, though paid accounts keep an encrypted copy in a personal History dashboard.
- Detection testing: The detector and humanizer are tested against common academic detection tools including Turnitin and GPTZero; the vendor notes accuracy varies with how much the original text has been edited.
- Cancellation: Plans are month-to-month and can be cancelled or downgraded at any time, with remaining word balances kept until the period ends.
Who It's For
GPTinf is aimed at students and academics who want to check essays and assignments before submission, educators reviewing work for AI involvement and plagiarism, and ESL writers seeking more natural English phrasing. It also targets freelance writers, bloggers, and marketing professionals who draft with AI assistance and want output that matches a human or brand voice, as well as business writers preparing reports without a templated AI tone.
FAQ
What is GPTinf?GPTinf is a free-to-start AI writing toolkit that includes an AI humanizer, AI detector, paraphraser, plagiarism checker, readability checker, grammar checker, and an essay writer, all accessible through a single website.
Is GPTinf free to use?Yes, every tool has a free tier that requires no registration; paid plans (Lite, Pro, and Unlimited) unlock higher word limits and additional features.
Which AI detectors does GPTinf test against?The company says its detector and humanizer are tested against tools commonly used in academic and professional settings, including Turnitin and GPTZero, and that accuracy depends on how heavily the original text has been edited.
Does GPTinf store or share submitted text?The vendor states submitted text is processed to generate output and is not stored, shared, or used for model training after the session ends; paid users get an encrypted personal history of their past humanizations.
Can plans be cancelled anytime?Yes, all plans are month-to-month and can be cancelled or downgraded in a couple of clicks, with remaining word balances available until the end of the billing period.
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