Grammarly Review (2026): Free vs Pro, Pricing and the AI Detector

Most people meet it as a green circle in the corner of a text box. This Grammarly review looks at what sits behind that circle in late 2026.

A lot has changed. The parent company took the name Superhuman, and the app picked up an AI detector, a humanizer and a set of writing agents. Meanwhile, the price list shrank to three plans.

So the testing behind this Grammarly review followed three questions. First, is the free plan still enough? Second, what does Pro really cost? Finally, how far can you trust its AI detector?

So, what is Grammarly? It is an AI writing assistant that reads along while you type. It flags grammar, spelling and punctuation errors, and it suggests clearer wording.

Is Grammarly AI? Yes, in two ways. Its checks have long relied on machine learning. In addition, it now includes generative AI that drafts, rewrites and replies from a prompt.

The company says more than 40 million people and 50,000 organizations use it. You may also see the name written as Grammerly or Gramarly, yet it is the same product.

The business behind it changed, too. Grammarly bought Coda in December 2024 and the email app Superhuman in June 2025. Then, in late October 2025, the whole company adopted the Superhuman name. Fast Company covered that rebrand and the new Superhuman Go assistant. However, the writing product keeps the Grammarly name.

Students, office workers and non-native English speakers get the most from it. Anyone who writes emails, reports or essays in English every day will see a benefit quickly.

Teams are a second audience. Pro includes a style guide, a brand tone and shared snippets, so a small company can keep its wording consistent.

On the other hand, it is a weak fit for people who write mostly in other languages. Likewise, novelists may find the suggestions too tidy for a personal voice.

The basic idea is simple. You install it once, and it then follows you into the places where you write. Four parts carry most of the value.

The grammar checker underlines problems as you type. You hover over a line, read the reason and accept the fix with one click. Because of this, corrections take seconds.

Free accounts get spelling and grammar fixes, and they can see the tone of a message. Pro goes further. It rewrites full sentences, adjusts tone on request and gives unlimited personalized suggestions.

The Grammarly extension runs in Chrome, Safari, Firefox and Edge. In addition, there are desktop apps for Windows and Mac, plus mobile keyboards for iPhone, iPad and Android.

How do you add Grammarly to Word? Install the desktop app, or use the add-in for Microsoft Office. For Google Docs, the browser extension is enough. After that, suggestions appear inside the document.

The Grammarly AI detector splits a text into sections and looks for patterns linked to AI writing. Then it shows a percentage for how much of the text appears to be AI-generated.

A basic scan is free on the website. Meanwhile, the AI Detector agent inside your documents needs Pro. A humanizer agent sits next to it and rewrites stiff, robotic sentences.

The Grammarly plagiarism checker compares your text with online sources and is part of Pro. Similarly, citation consistency checks are reserved for paying users.

The newer agents handle narrower jobs. AI Grader estimates a grade, Citation Finder looks for sources, and Reader Reactions predicts how a reader may respond. Furthermore, Authorship labels which parts you typed, pasted or generated with AI.

In daily use, the proofreading is still the best reason to install it. It catches typos, missing commas and agreement errors that built-in spell checkers miss. Moreover, it works almost everywhere, which rivals struggle to match.

The suggestions are not always right, though. Clarity rewrites can flatten a sentence that was fine. Therefore treat each one as advice, and reject the ones that change your meaning.

Is Grammarly AI detector accurate? The company claims 99% detection accuracy and a number one ranking on the independent RAID benchmark. However, the same page admits that no AI detector is 100% accurate. It also tells users not to rely on the result alone.

We found no independent test that confirms the 99% figure for everyday essays. As a result, this Grammarly review treats the score as a hint. No grade or job decision should rest on it.

Does Grammarly count as AI at school? That depends on the policy. Fixing spelling is rarely a problem. Still, generative rewrites and the humanizer can cross the line, so ask before you use them on graded work.

The generative side is the weakest part. Prompts are capped each month, and long drafts come out more generic than those from a dedicated chatbot. In addition, the full suggestions are built for English.

The plan list is short. Every price in this Grammarly review was read on the official plans page on October 8, 2026, and two of them come from third-party pricing guides.

Is Grammarly free? Yes. The free plan fixes spelling and grammar, shows your tone and includes 100 AI prompts a month. For many people, that is enough.

How much is Grammarly Pro? It costs $12 a month when you pay $144 for a year. However, the same plan costs $30 if you pay month by month. So the yearly plan is the real offer.

Pro starts with a 7-day free trial, and the page promises a reminder email two days before it ends. Even so, pricing guides report users who missed the billed annually note and were charged $144 at once. Therefore set your own reminder.

There is no general promo code. Instead, the guides mention a 50% student discount that needs verification and covers one billing period. Refunds are also limited, so cancel before the renewal date.

These two are compared more than any other pair. Grammarly is the stronger proofreader, with deeper feedback on tone and clarity, and it works inside more apps.

QuillBot, on the other hand, wins on rewriting. Its paraphraser has more modes, and it adds a summarizer and citations. Our QuillBot review covers its limits and prices.

So choose Grammarly if you mostly polish your own writing. Pick QuillBot if you often rework or shorten text and want a lower yearly bill.

Is Grammarly legit? Yes. It has been on the market since 2009, it publishes its plans, and its apps sit in the official stores. In addition, large companies such as Atlassian and Zoom appear on its customer list.

Is Grammarly safe? For everyday writing, it is as safe as other mainstream cloud tools. Still, your text is processed on its servers. For that reason, think twice before you paste confidential or client material.

How do you turn off Grammarly? Click its icon in the browser toolbar and switch it off for the current site. As a result, you can keep it away from sensitive pages without removing it.

Jenni AI is built for research papers and essays. It suggests the next sentence, manages citations and chats with your PDFs. Our Jenni AI review has the details.

Pick it when the hard part is drafting an academic text, not polishing one.

HIX AI bundles a humanizer with an agent workspace for research, slides and media. Our HIX AI review covers its credits and test results.

It suits people who want one subscription for many AI tasks instead of a proofreader.

Undetectable AI focuses on one job. It humanizes AI text and checks it against several detectors at once.

Consider it if humanizing is all you need. However, it will not replace a grammar checker.

Pros

• Accurate grammar, spelling and punctuation checks with a clear reason for every fix
• Works in browsers, desktop apps, Microsoft Office, Google Docs and mobile keyboards
• A free plan that covers basic proofreading, tone detection and 100 AI prompts a month
• Pro adds full-sentence rewrites, a plagiarism checker, an AI detector and writing agents in one plan
• A 7-day free trial of Pro with a reminder email before it ends

Cons

• Monthly billing costs $30, which is 2.5 times the $12 annual rate
• The annual plan charges $144 upfront, and refunds are limited
• The 99% AI detector claim comes from the company, and it admits no detector is fully accurate
• Full suggestions are built for English, so other languages get far less
• Clarity rewrites can flatten a personal voice and sometimes change the meaning

For proofreading, yes. Grammarly remains the easiest way to clean up English writing across every app you use. In addition, the free plan is good enough for most casual writers.

Pro is a closer call. It is fair value at $12 a month on the yearly plan. At $30 a month, though, it is hard to recommend unless you need the plagiarism checker every week.

The short answer from this Grammarly review: start free, try Pro for seven days, and set a reminder before the trial ends. The company may want to be Superhuman now. Even so, its most useful trick is still the humble one, which is catching the mistake before anyone else reads it.

To see how it stacks up against drafting assistants, open our guide to the best AI writing tools, with prices and limits side by side.

In addition, the best AI humanizer tools collection compares dedicated humanizers, and our GPTZero review tests a detector built for teachers.