Writing assistant with AI detection
Best Grammarly AI Detector Alternative
Grammarly is the dominant grammar and writing assistant, and it now includes an AI detector plus Authorship — a provenance feature that records how a document was written (typed, pasted, AI-generated) inside supported editors. The detector itself returns an overall percentage of text that reads as AI-generated. Detection features sit inside the broader Grammarly account ecosystem.
Why switch from Grammarly AI Detector?
Sentence-level evidence: Grammarly’s detector reports an overall percentage, while aicheckr shows which specific sentences score high and why.
No account or extension required: paste text at aicheckr and get a result; Grammarly’s detection lives inside its signed-in ecosystem.
Works after the fact: Grammarly Authorship is powerful but only tracks documents written where it was installed and active from the start. aicheckr analyzes any finished text from anywhere.
Verification extras: citation checking and hallucination detection alongside the detector — outside Grammarly’s scope.
Grammarly AI Detector vs aicheckr: side by side
| Feature | Grammarly AI Detector | aicheckr |
|---|---|---|
| AI detection output | Overall percentage of likely AI text | Overall score plus per-sentence probabilities and named signals |
| Writing provenance tracking | Yes — Authorship records how a document was composed in supported apps | No — analyzes finished text instead |
| Grammar & style checking | Yes — best-in-class, with tone and clarity suggestions | Yes — basic free grammar checker |
| Setup required | Grammarly account; Authorship needs the editor integration from day one | None — paste any text, no signup for the first checks |
| AI humanizer | No — Grammarly focuses on polishing, not rewriting to sound human | Yes — built-in humanizer and paraphraser |
| Pricing | Free tier; paid plans from roughly $12/month on annual billing | Free; Pro $10/month |
Our verdict
Grammarly remains the best writing assistant, and Authorship is a genuinely clever answer to the provenance problem — if you set it up in advance. As a detector, though, its single percentage is thin. aicheckr is the better pick when the question is "which parts of this existing text look AI-written?" — free, no account, sentence by sentence.
Judge it on your own text
Paste up to 500 words — no account needed — and see per-sentence AI probabilities with a confidence band in seconds.
Try the free AI checker