Grammarly is the writing assistant most companies already have: spelling, grammar, tone and full-sentence rewrites in a million apps. Its paid plans add a brand tone, a style guide, an AI-text detector and a personal voice profile for rewrites.
BeigeCheck is a read-only connector that gives Claude, ChatGPT and Microsoft 365 Copilot your company’s approved facts and voice before they write, then scores the draft and checks every claim against those facts. Grammarly acts after the model writes; BeigeCheck acts before it writes and again after.
Side by side
Works inside your own AI tools
- Grammarly
- Partly. Its browser extension and desktop apps suggest changes as you type on websites, so it can act on text in an AI tool’s window. Nothing from your style guide or facts reaches the model’s context, and no MCP connector for Grammarly’s checks is shown on its pages.
- BeigeCheck
- Claude and ChatGPT on every plan; Microsoft 365 Copilot from Business up. The model gets your facts and voice before it writes.
Other places it works
- Grammarly
- Every major browser, Windows and Mac, iPhone and Android, and more than a million apps including Google Docs, Word, Gmail and Slack. APIs for AI detection, plagiarism and a writing score.
- BeigeCheck
- A web API for your own systems on Business Integrated and Enterprise.
What it checks
- Grammarly
- Spelling, grammar, clarity, tone and inclusive language; a style guide of company rules (one on Pro, unlimited on Enterprise); plagiarism; an AI-text detector that gives a percentage and which Grammarly says shouldn’t be used “as an objective source of truth”.
- BeigeCheck
- The Beige-ometer on every draft: how authentic it reads and how well it fits the voice, with the sentences to change and a fix for each; Citability on public formats; a claim check against your approved facts. It never guesses who wrote the text.
Company voice
- Grammarly
- Yes: a brand tone that labels detected tones on-brand or off-brand (one on Pro, unlimited on Enterprise), plus the style guide.
- BeigeCheck
- Yes: an approved company voice per kind of writing, a glossary and house rules.
Personal voice
- Grammarly
- Yes: a voice profile detected from your writing and updated as you type, used for “Rewrite in my voice”, on Business and Enterprise. Pro users get custom voices in the Humanizer from a 200-word sample.
- BeigeCheck
- Yes: each person’s own voice, built only from writing they’ve done themselves, on every plan.
Approved facts with sources
- Grammarly
- Knowledge Share shows definitions of terms, acronyms and project names on hover. Checking a draft’s claims against approved facts isn’t shown on its pages.
- BeigeCheck
- Yes: approved facts, each with its source and version, in six areas; every claim in a draft checked against them.
Learning
- Grammarly
- The personal voice profile updates as you write. Changes to brand rules from a team’s decisions, or any approval step, aren’t shown on its pages.
- BeigeCheck
- Proposes changes from your documents and from the edits people keep making; an approver decides every one.
Pricing model
- Grammarly
- Per member, monthly or annual.
- BeigeCheck
- Flat price per company with unlimited people, metered on units a month. The rule-based checks are unlimited.
Entry price
- Grammarly
- Free plan. Pro $12 a member a month billed annually, $30 monthly, up to 149 seats. Enterprise quoted, sold through Superhuman Go.
- BeigeCheck
- Starter $249 a month billed yearly ($293 monthly); Business $535; Business Integrated $1,062; Enterprise from $2,500. Also in pounds and euros.
Trial
- Grammarly
- A free plan, and a Pro trial whose length isn’t stated on the plans page.
- BeigeCheck
- 7 days on Starter and 14 on Business, from your first check, and you don’t need a card.
Where your data is
- Grammarly
- AWS in the US. SOC 2 Type 2, ISO 27001, 27701 and 42001, HIPAA.
- BeigeCheck
- Database in Ireland, servers in London. The AI model for checks runs with Anthropic in the United States.
Status page
- Grammarly
- Yes, status.grammarly.com.
- BeigeCheck
- Yes, and it’s checked every five minutes.
Where they overlap
Both hold a company voice and a personal one. Grammarly’s brand tone and style guide are the company layer; its voice profile is the personal one, and like BeigeCheck’s it’s built from the person’s own writing. Both suggest specific changes in the place you’re working rather than sending you somewhere else. And both put a number on a draft, though they’re measuring different things.
Grammarly covers far more ground. It runs in a million apps, on the phone, in Gmail and Slack and Jira. Grammar and spelling are its job, and BeigeCheck doesn’t attempt them.
A company with Grammarly Pro has already solved typos, tone labels and a single style guide for $12 a head, and nothing on this page says it should stop.
Where they differ
The first difference is timing. Grammarly acts on words after the model has written them. BeigeCheck acts first, by giving Claude, ChatGPT or Copilot your approved voice, glossary, house rules and facts before it writes, and then again on the draft. A tone label can tell you a paragraph reads as formal; it can’t tell you the figure in it is from last year’s price list.
The second is what the number means. Grammarly’s AI detector estimates how much of a text a model wrote, and Grammarly itself says not to treat that as truth. The Beige-ometer never asks who wrote it. It scores how a reader will receive the text, quotes the sentences that read as machine-made, and scores how well the draft fits the voice it’s meant to be in. A human-written paragraph full of stock phrases scores badly on the Beige-ometer and passes the detector.
The third is facts. Knowledge Share tells a colleague what an acronym means when they hover over it. BeigeCheck holds the facts the company has approved, each with its source, and checks every claim in a draft against them, with an approver behind every change.
And the fourth is price shape. Grammarly charges per member and caps Pro at one brand tone and one style guide. BeigeCheck charges the company a flat price with unlimited people, and every plan has the company voice, the personal voice and the facts.
Who each suits
Grammarly suits almost everyone for what it does: a company that wants clean, consistent English in every app its people use, a style guide applied as they type, and tone feedback at a low per-seat price. Keep it.
BeigeCheck suits a company whose people write in Claude, ChatGPT or Copilot and whose problem starts before the typos: the model doesn’t know the company’s facts, the drafts sound like everyone else’s, and nobody checks the claims. Many companies will run both.
Last checked 3 November 2026, against Grammarly’s and Superhuman’s own plans, support, developer and compliance pages. Prices and features change, so check its pages before you decide.