Fifteen years of catching typos and fixing comma splices built Grammarly into one of the most installed browser extensions on the web. Then the company decided that wasn't enough.
Since launching its AI writing features under the "Grammarly Go" banner in April 2023, Grammarly has been competing in a market it didn't start - and one where its advantages are harder to hold. The company that built its reputation on reliability is now selling something harder to trust.
What Made Grammarly Good
Grammarly's original value proposition was specific: paste text in, get errors flagged. The suggestions were narrow and defensible. A comma was missing. A sentence was passive when active would serve better. You could accept or reject and move on. The tool was right more often than it was wrong, and it knew when to stay quiet.
AI writing assistance works differently. Instead of flagging mistakes, it suggests rewrites. Those suggestions don't just correct - they restructure whole sentences and sometimes whole paragraphs. In the process, they can strip out the voice and specific word choices that made your writing yours.
Users noticed. Grammarly's AI suggestions were pushing writing toward a generic, flattened tone. The tool that used to make writing more precise was making it sound like everyone else's. Call it the "sloppelganger" effect: a version of your text that superficially resembles what you wrote but is blander, vaguer, and less specific. It passes at a glance. It just isn't good.
That's a real product problem for a company that built a brand on making writing better, not just different.
The $13B Question
The business challenge is harder to dismiss. Grammarly raised $200M at a $13B valuation in 2021 - a number that priced in a future where the company owned AI writing assistance, particularly in enterprise. That future hasn't arrived the way anyone expected, and Grammarly now competes against tools backed by companies spending orders of magnitude more on the underlying technology.
Grammarly's AI relies on third-party models rather than technology it owns outright. That means its competitive position depends on partnerships and integrations rather than core model quality - a position that erodes as those same models get cheaper and competitors embed writing assistance directly into the tools people already use.
Google Docs, Microsoft Word, Notion, and most email clients now ship with AI writing built in. Grammarly's distribution advantage - installed on tens of millions of browsers - matters less when the destination apps themselves have become the competition.
The company still has real things going for it: brand recognition, a large free user base, and a strong track record in professional and educational settings. The core grammar checking still works. For non-native English speakers who rely on it for correctness rather than style, it remains one of the better options available.
But its path to justifying a $13B valuation requires a convincing answer to what Grammarly does that native AI features don't - and that answer hasn't been clearly demonstrated yet.