GPTinf

About the startup

AI drafts read like AI. Same sentence rhythm, the same "furthermore," the same flat tone — and editors, clients, and detectors all pick up on it. GPTinf is an all-in-one AI writing toolkit that handles that in one place: AI Humanizer, AI Detector, Plagiarism Checker, Grammar Checker, Paraphraser, and Readability Checker. AI Humanizer — restructures sentences at the grammatical level instead of swapping synonyms, so your meaning and register survive the rewrite. 8 modes (Standard, Academic, Formal, Simple, Informal, Expand, Shorten, Creative), paste text or upload PDF, Word, and plain text files, and freeze any words or phrases you don't want touched — unlimited freeze keywords on every plan, including free. AI Detector — free, unlimited, no account required. Cross-checks against 8 detectors (Turnitin, Originality.ai, GPTZero, Copyleaks, Sapling.ai, Crossplag, Gowinston.ai, ZeroGPT) with pass/fail per detector and color-coded segments. It also runs automatically after every humanization, so you see the score without clicking anything. Plagiarism Checker — sentence-level source attribution with exact URLs and match percentages. In our own head-to-head test on the same passage it surfaced 152 sources; the next-closest tool found 14. Grammar Checker — self-hosted engine, so your text never passes through third-party servers. Catches grammar, spelling, and the contextual mistakes a spell-checker misses. Paraphraser — 7 writing styles, same rewriting engine. Readability Checker — Flesch score mapped to a grade level, built specifically for AI-generated content. Free tier: 300 words per request, no account needed, file upload and the full detector included. Paid plans start at $9.99/mo for 5,000 words, $24.99/mo for 25,000. Built for content teams, freelancers, bloggers, SEO writers, students, and non-native English speakers who want the speed of AI without the tells — and who'd rather check their own text than find out after they publish.