How to Use Grammarly's AI Checker: A Step-by-Step Guide

Where Do You Find Grammarly's AI Checker?

Grammarly's AI detection score lives inside the same editor as its grammar and clarity suggestions, not as a separate standalone tool. Open a document in the web editor at app.grammarly.com, the desktop app, or Grammarly for Word or Google Docs, and the AI-generated text indicator appears in the document's Insights or Overview panel alongside readability and correctness scores. It will not show up on very short snippets — Grammarly needs a reasonable amount of text to generate a reading, so a single sentence or a two-line comment usually will not produce a score at all. The feature also is not included in every subscription tier, so if you open a document and do not see an AI score anywhere in the sidebar, check your plan before assuming something is broken. The browser extension that runs on Gmail, Google Docs, or a CMS text box typically only surfaces grammar and clarity corrections — the AI score is a document-level reading, so you generally need to be working inside a full Grammarly document to see it rather than a comment box on another site.

1. Open your document in Grammarly's web editor, desktop app, or a supported document integration.
2. Look for the AI-generated text indicator in the Insights or Overview panel, not in the inline suggestion feed.
3. Add more text if no score appears — short excerpts usually will not generate one.
4. Confirm your Grammarly plan includes AI detection if the indicator never loads.

How Do You Run a Document Through Grammarly's AI Checker?

The order you do things in changes what the score means. If you paste a finished draft and check the score before accepting any of Grammarly's own suggestions, you get a baseline reading of your original writing. If you accept a batch of grammar and clarity suggestions first and check the score afterward, you are reading a slightly different, Grammarly-smoothed version of the same text — and that smoothing can shift the number in either direction. Neither approach is wrong, but conflating them leads to confusion, which is why most of the frustration people report with Grammarly's AI checker actually traces back to not knowing which version of their text produced which score.

1. Paste your complete draft into a fresh document instead of checking a partial excerpt.
2. Let the editor finish its full pass before reading the AI score — a partial load can show an incomplete reading.
3. Record the score before accepting any grammar or clarity suggestions, so you have an unedited baseline.
4. Re-check after major edits if you want to see how those specific changes affected the reading.

What Does the Grammarly AI Score Actually Mean?

Grammarly's AI checker returns a percentage-style estimate of how closely a piece of text matches patterns associated with AI-generated writing. Under the hood, that estimate is built from signals like perplexity — how predictable each word choice is given what came before it — and burstiness, which measures how much sentence length and structure vary across a passage. AI-generated text tends to sit in a narrower, more predictable band on both measures; human writing tends to wander more. The score is a probability estimate, not a verdict. It is built from statistical patterns in the text itself, and it has no access to your drafts, your writing history, or the process you actually used to produce the document. A score of 20% does not mean one-fifth of your document was written by AI — it means the overall text sits closer to the human end of the model's scale than the AI end, and treating the number as a literal proportion is a common misreading that leads people to argue with a result that was never making that claim in the first place.

Grammarly's AI score is a statistical estimate based on word predictability and sentence rhythm — not a record of how the text was actually written.

How Should You Read Grammarly's Highlighted Sections?

The overall percentage is the least useful part of the output on its own. What matters more is which sentences or paragraphs are contributing to that number, and Grammarly's interface will typically point to those passages directly rather than leaving you to guess. A single flagged sentence buried in an otherwise low-scoring document is usually just noise — short, generic-sounding phrases get flagged on their own fairly often. A cluster of flagged sentences across several consecutive paragraphs is a stronger signal worth reading closely. When you see that pattern, read the flagged passages the way an editor would: are they carrying specific detail, a concrete example, or a claim you can trace to a source, or are they mostly filler that could belong to almost any document on the topic?

What Are the Limits of Grammarly's AI Checker?

Grammarly's AI checker does not know your assignment, your job, your usual writing style, or your draft history — it only sees the text in front of it. That creates two predictable failure modes. Formal, polished, or evenly structured writing — scholarship essays, technical summaries, and work by non-native English speakers in particular — can score higher than expected simply because that kind of writing already sits closer to the statistical patterns the model associates with AI output. In the other direction, AI-assisted text that has been heavily rewritten, given specific examples, and varied in rhythm can score lower than expected, because the surface-level smoothness that gives the model its signal has been edited away. Grammarly's score also does not predict what a different tool, such as Turnitin or an institution's own detector, will report on the same text, since each system is trained and calibrated differently.

A detector built on statistical patterns cannot see intent — it can only describe how closely your text resembles other text it has seen before.

Does a Low Score Mean Your Writing Is Safe to Submit?

Not by itself. A low Grammarly AI score tells you that, at the moment you ran the check, your text did not resemble the statistical patterns the model associates with AI output. It does not confirm authorship, and it will not necessarily match what a different detector says about the same document. How much weight the score should carry depends entirely on the stakes. For a blog draft or an internal memo, a low score plus a quick read-through is usually enough. For a graded assignment, a client deliverable, or anything tied to an academic integrity policy, a single score from a single tool is thin evidence on its own, and treating it as a guarantee is where most avoidable problems start. This matters most for people whose natural writing style already reads as formal or evenly paced, since a single low reading can create false confidence right before a document goes somewhere a second, more critical review might happen.

How Do You Cross-Check a Grammarly Result Before Submitting Work?

Because no detector, including Grammarly's, is built to be the final word on a document, the more reliable approach is to treat its score as one data point and confirm it against a second, independent reading before anything important goes out. A tool that shows sentence-level highlights rather than just a single percentage — NotGPT among them — lets you see whether the same specific passages get flagged twice, which is a much stronger signal than either score alone. If two different tools point at the same sentences, that is where your revision time is best spent. If they disagree sharply, you are likely dealing with genuinely ambiguous text, and documenting your process becomes more useful than chasing a lower number.

1. Run the same draft through a second AI detector that shows sentence-level results, not just an overall score.
2. Compare which specific passages both tools flag, rather than comparing only the two percentages.
3. Revise the sentences both tools agree on by adding concrete detail, a specific example, or a source you can point to.
4. Keep your original draft and version history saved in case you need to show your process later.

What's a Practical Workflow for Using Grammarly's AI Checker?

Put together, a workflow that avoids most of the confusion looks like this: save your original draft before running any editing tool, paste the full text into Grammarly rather than a short excerpt, read the score before accepting suggestions so you have a clean baseline, then look at which specific sentences are flagged rather than fixating on the percentage. If the stakes are meaningful — a grade, a client relationship, a publication — run a second detector with sentence-level output and revise only the passages both tools agree on. NotGPT is built for that second-opinion step: it highlights the exact sentences driving an AI-likelihood score and pairs that with a Humanize option if a passage needs to be rewritten in your own voice rather than just resubmitted as-is. Used this way, Grammarly's AI checker becomes one useful signal in a short process instead of a single number you either trust or don't.