Grammarly is a long-standing AI writing assistant that checks grammar, spelling, punctuation, tone, and clarity, and increasingly generates and rewrites text outright via its GrammarlyGO/generative features. It works as a browser extension, desktop app, and mobile keyboard, and integrates with Google Docs, MS Office, and most web forms. Pricing in 2026 is three-tiered: Free ($0, basic grammar/spelling/tone checks with roughly 100 AI prompts/month), Premium/Pro (around $12/month billed annually, or up to $30/month billed monthly — jumps to 2,000 AI prompts, full-sentence rewrites, plagiarism detection, and vocabulary/clarity suggestions), and Business (~$15–25/member/month, adding brand tone controls, team analytics, and SSO). Following Grammarly's 2025 acquisition of Superhuman (email) and Coda (workspace), the parent company rebranded itself "Superhuman" in October 2025 and now bundles all three products, plus a new proactive assistant called Superhuman Go, into a broader suite.