PromptAI Tools

Prepostseo is a long-running web toolbox offering 150+ free online SEO utilities and AI writing assistants in one place. It bundles a plagiarism checker, paraphrasing tool, grammar checker, summarizer, AI essay writer, image-to-text OCR, humanizer, domain authority checker and dozens more, with paid Premium plans for heavier usage.

QuillBot is an AI writing suite best known for its paraphrasing tool. Users paste or type text and have it rewritten in different tones and styles, while companion tools handle grammar checking, summarizing, citations, plagiarism checks and AI content detection. It is widely used by students, writers and professionals.

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モード・トーン・関連ツールを備えたAI言い換え＆ライティングスイート

無料のAIライティングツールに、エディタ・Autoblog・ナレッジベースを追加

paraphrasing.io is a browser-based AI paraphrasing tool that rewrites essays, emails, sentences, and paragraphs in seven modes, backed by a suite of related writing utilities.

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AIによるエッセイ執筆・言い換え・盗用チェックを一か所で

数秒で、トーンが整ったビジネスメールを作成

TheToolBus is a free online utility hub offering a large library of browser-based tools for PDF editing, image conversion, file conversion, calculators, text manipulation, and everyday productivity tasks. Almost everything runs without signup or watermarks.

ZeroGPT is an AI content detection platform with a text AI detector, AI image and video detectors, AI humanizer, plagiarism checker, and a set of writing tools including paraphraser, summarizer, grammar checker, translator, and citation helper.