QuillBot’s flagship feature is its AI paraphraser, which can. reword sentences, paragraphs, or entire articles while preserving the original meaning. It intelligently restructures sentences (not just swapping words) to improve fluency and clarity. Users can choose from multiple writing modes to tailor the tone and style of the output – the free version includes Standard and Fluency modes, while Premium unlocks modes like Formal, Simple, Creative, Academic, Expand, Shorten, plus even custom modes. A built-in synonym slider lets users control how much the text is changed: sliding right introduces more varied vocabulary (more creative output), while sliding left keeps the phrasing closer to the original for accuracy. This tool is especially useful for avoiding repetitive wording and adapting content to different audiences or contexts.

QuillBot includes a grammar checker that proofreads text and identifies grammar, spelling, and punctuation errors. It provides suggestions to fix basic mistakes (in the free version) and more advanced grammatical issues in the premium version. This feature helps writers produce error-free text, much like dedicated tools (e.g. Grammarly), by highlighting problem areas (such as subject-verb agreement, tense consistency, punctuation, etc.) and offering corrections. It’s a handy tool to improve writing mechanics and ensure professionalism in essays, emails, and documents.

QuillBot’s summarizer can condense long articles or papers into a concise overview of key points. Users can input a passage (the free plan allows summarizing up to ~1,200 words at a time) and the tool will generate a shorter paragraph or list of the main ideas. This helps readers quickly grasp the essence of lengthy texts without reading them in full. Premium users can create longer or custom-length summaries for more control. The summarizer is particularly useful for students reviewing research, professionals extracting reports, or anyone who needs to distill information efficiently.

For academic and research writing, QuillBot offers a citation generator that formats references in standard styles like APA, MLA, and Chicago. Users can enter details of a source (or use a URL/DOI) and QuillBot will produce both full and in-text citations automatically. This saves time and ensures the bibliography is properly formatted. Notably, this citation tool is free for all users (no Premium required), making it a handy standalone resource for students compiling references.

QuillBot includes a plagiarism checker (available with a Premium subscription) that scans your writing against a large database of webpages and publications. It highlights any passages in your text that closely match existing sources, helping you identify unintentional plagiarism before submitting work. This feature is invaluable for academic writers and researchers to ensure the originality of their work. However, it’s worth noting that QuillBot’s plagiarism checker, while useful, is not as exhaustive as dedicated plagiarism tools like Turnitin– it’s intended for quick checks to prevent accidental plagiarism as part of the writing process.

QuillBot has expanded its toolkit with several AI-driven utilities. An AI Detector (or “AI writing checker”) can analyze text and estimate the likelihood that it was AI-generated, providing writers with insight into how “human” their writing appears. Conversely, an AI Humanizer tool can take AI-generated content and rephrase it to sound more natural and human-like. There’s also a built-in Translator supporting 50+ languages for translating text, and even an AI Chat feature (a chatbot similar to ChatGPT) for brainstorming ideas or getting writing assistance. Many of these supplementary tools (like the AI detector, translator, and citation generator). re available to free users, while Premium grants unlimited or enhanced usage of them. This ecosystem of tools makes QuillBot a versatile platform for various writing-related tasks beyond just paraphrasing.