SlopgaugePour in an essay.
Slopgauge marks the sentences that read like chatbot writing, measures how much of the text does, and names the tells behind it. Free, no account, and nothing you paste is uploaded. A whole assignment? Check a class at once.
No detector can prove who wrote a text. About 1 in 100 essays by people is still called “Likely AI-written”, so treat a report as a reason to talk with the writer, never as proof on its own.
How it measures.
Every sentence is scored with its neighbours, about 60 words at a time, by a small model trained on about 120,000 texts by people and by GPT-4o, Claude, Gemini, Llama and others. It reads word choice, word pairs, punctuation and sentence rhythm, together with Slopgauge’s named tells.
The verdict scores the whole text in parts of about 220 words. The gauge shows the share of words in sentences that read as AI-written. With their own writing pasted in, a neural style model (LUAR) also checks whether each part sounds like them.
Tested on 2,999 school essays by students in grades 6 to 12, it called 1 in 100 “Likely AI-written” and caught 72 of 100 essays written by AI on the same prompts. In essays that were half the student’s and half AI, it marked 44% of the AI half and 2% of the student’s half.
How often people’s writing scores high depends on the kind of text, so the thresholds are set separately for school essays, college essays, stories, news and online posts. Pick the kind next to the word count. Short texts are harder: under a few hundred words, results are less reliable. The research it’s built on.