Grammarly acquires email startup Superhuman to expand beyond grammar and dominate AI work tools

Grammarly is making its boldest move yet to shed its reputation as just a grammar-checking app. The company has acquired Superhuman, the sleek email startup known for speed, AI features, and an invite-only mystique that once made it Silicon Valley’s most hyped productivity tool, according to an exclusive report from Reuters.

The deal is part of Grammarly’s broader push to build an AI-first productivity suite. Financial terms weren’t disclosed, but Superhuman was last valued at $825 million in 2021 and now brings in around $35 million a year.

The acquisition follows Grammarly’s recent $1 billion raise from General Catalyst—money it’s now using to reimagine workplace tools. The company says it’s working on a name change and a broader identity that reflects its shift beyond just grammar.

Superhuman, founded by Rahul Vohra, raised over $110 million from backers like IVP and Andreessen Horowitz. It built a loyal following among professionals who wanted a faster, smarter email experience. Its users send and respond to 72% more emails per hour, and AI-written messages have jumped 5x over the past year. But it hasn’t been an easy ride. With Google and Microsoft stuffing more AI into Gmail and Outlook, the competition has grown fierce.

“Email continues to be the dominant communication tool for the world. Professionals spend something like three hours a day in their inboxes. It’s by far the most used work app, foundational to any productivity suite,” said Shashir Mehrotra, Grammarly’s CEO. “Superhuman is the obvious leading innovator in the space.”

Mehrotra previously co-founded Coda, which Grammarly acquired last year to build out tools for writing, planning, and collaboration. Now, he says email is the next piece of the puzzle.

As part of the deal, Vohra and more than 100 Superhuman employees will join Grammarly. The product and brand will stay alive, for now, Reuters reported.

“The Superhuman product, team, and brand will continue,” Mehrotra told Reuters. “It’s a very well-used product by tens of thousands of people, and we want to see them continue to make progress.”

Vohra said the deal gives Superhuman access to more firepower. That includes building deeper AI features and expanding into calendars, tasks, and enterprise collaboration.

The goal is to connect Grammarly’s AI agents with Superhuman’s email layer. Users could pull in insights from across their inboxes, documents, and workflows, cutting down the time spent searching, replying, or context-switching. The broader vision is to compete head-on with tech giants like Salesforce, Google, and Microsoft, all of whom are racing to own the future of work through AI.

Grammarly, with over 40 million daily users and over $700 million in annual revenue, is betting that owning the communication layer will give it an edge as it builds a full stack of AI work tools.

The name “Grammarly” might soon be a small part of what the company does.