DetectGPT

DetectGPT is a free, no-account web checker that scores pasted text or a public URL for machine-sounding prose, highlights flagged lines, and includes a web-overlap plagiarism tab. Runs are capped at 3,000 words.

DetectGPT is a browser-based checker that estimates how much of a piece of writing sounds machine-generated. A user pastes text, uploads a .txt document, or enters a public page URL, and the tool returns a percentage along with highlighted passages. Flagged lines appear in light yellow once they pass 20%, then shift to yellow, orange or red as the signal strengthens. The brand is not tied to one model: it scores prose from ChatGPT, Claude, Grok, Gemini and other language models, and it only looks at the finished draft, never at an account or the original prompt. The tool is aimed at people who want a look at their own writing before someone else runs a check. Students can review a paper they partly drafted with a model, writers and teachers can spot the generic transitions and even sentence rhythm that make a post read as generated, and second-language writers can use the score to vary phrasing. The site is candid about interpretation: the percentage is a share of prose that looks machine-made, not a probability of misconduct, and scores under roughly 20% are described as noisy. It cannot prove authorship, read images or scanned PDFs, or reproduce a school's private report. In practice a run takes under a minute. Input needs at least 50 words and is capped at 3,000 words per run, so longer work has to be split into chunks. Pasted text is scored in the browser and history stays on the device, while URL analysis has the site's servers fetch the page. Results can be shared through a link. A separate Plagiarism Checker tab compares up to 3,000 words against public web pages and lists matching phrases with source links. Among alternatives, DetectGPT sits beside public dashboards such as ZeroGPT and institutional systems such as Turnitin's AI indicator. Its pitch is access: free, no account, no daily cap on checks, and no campus login. It is independent of both competitors and works best as a comparable style check rather than as evidence in a dispute. Accuracy is strongest on English.