RealWrite vs Grammarly: AI Detector and Humanizer Compared

Grammarly is a writing assistant with an AI detector and humanizer added. RealWrite is built around those two tools. Here is how they differ and who each suits.

By RealWrite Editorial Team3 min read

On this page
  1. Side by side
  2. Where Grammarly is ahead
  3. Where RealWrite is ahead
  4. What both say about detectors
  5. Which one should you choose?
  6. FAQ

Grammarly is the better pick if you want one writing assistant everywhere you type, with grammar checks, a free AI detector on the web and a light-touch humanizer in six languages. RealWrite is the better pick if checking and rewriting AI text is the main job: its detector explains each flagged sentence, its humanizer writes in 41 languages, and a meaning check after every rewrite flags changed numbers, names, quotes and citations.

A disclosure: RealWrite is our product. Grammarly details come from its AI Detector and AI Humanizer pages, its plans page and its support centre, checked on 21 October 2026. Grammarly is now part of Superhuman, which also agreed to acquire GPTZero in June 2026.

Side by side

RealWrite Grammarly
Free AI detector 500 words every day, 100 without an account Web tool, up to 25,000 characters
Detector in your documents No (web and iPhone app) Google Docs, Word and Grammarly's editor, on Pro
How results are shown A score, a category and an explanation for each flagged sentence A share of the text that appears AI-generated, with segments marked
Free humanizer 300 words every day Free web tool and a Humanizer agent
Humanizer languages Output in 41 languages 6 (English, Spanish, French, German, Portuguese, Italian)
Meaning check After every rewrite Not offered
Paid plan From $14.99/mo, or $9.99/mo yearly (30,000 words) Pro $30/mo, or $144/yr ($12/mo)
Grammar checking No Yes, its core product
Platforms Web, iPhone app Windows, Mac, iPhone, Android, browsers, Google Docs, Word

Where Grammarly is ahead

It is everywhere you write. Grammarly runs in browsers, Google Docs, Word, on desktop and on mobile. RealWrite is a website and an iPhone app.

Grammar and style in the same plan. Grammarly Pro is a full writing assistant. RealWrite does not check grammar.

Authorship reports. Grammarly can record how a document was written and produce a report, which helps if you need to show your own work. RealWrite has no equivalent.

A cheaper yearly price for heavy users. Pro is $12 a month billed yearly, with no monthly word limit stated.

Where RealWrite is ahead

It tells you why. RealWrite's AI Detector explains each flagged sentence, for example uniform sentence length, stock transitions or hedging, and suggests a fix. Grammarly shows which parts appear AI-generated and a percentage.

A detector and a humanizer that work together. You can rewrite only the flagged sentences, accept or reject each change and check again. Grammarly notes that text rewritten by its own humanizer will likely be flagged by its own detector.

More languages for rewriting. RealWrite's humanizer writes in 41 languages; Grammarly's in six.

A meaning check. After every rewrite RealWrite flags any number, name, quote, citation or link that changed. For essays and reports that is the difference between a natural rewrite and a wrong one.

Free every day. 300 humanizer words and 500 detector words renew daily on a free account.

What both say about detectors

Grammarly says its score "should not be used as an objective source of truth", and that its humanizer "is not intended to bypass AI detectors". We agree with both points. Detectors disagree with each other and change with updates, as our guide to AI detector false positives explains. Use either tool to make the writing read like you, not to chase a score.

Which one should you choose?

  • Choose Grammarly if you want grammar, style and AI tools in every app you write in, or need authorship reports.
  • Choose RealWrite if you want to see exactly which sentences read as AI, rewrite them in one of 41 languages and make sure the facts survived.
  • Use both if you already pay for Grammarly: check and rewrite drafts in RealWrite's free daily allowance, and keep Grammarly for grammar.

For more options, see our GPTZero alternatives and best AI humanizers comparisons.

Frequently asked questions

Is Grammarly’s AI detector free?
Grammarly’s web AI detector is free and takes up to 25,000 characters. Detection inside Google Docs, Word and Grammarly’s own editor is part of Pro, which costs $30 a month or $144 a year.
Does Grammarly’s detector flag text rewritten by Grammarly?
It can. Grammarly’s support centre says text rewritten by its own paraphraser or humanizer agents will likely be flagged as AI-generated.
Which is better for humanizing AI text, RealWrite or Grammarly?
Grammarly’s humanizer keeps the most of your original wording and works in six languages. RealWrite rewrites more, works in 41 output languages, lets you accept or reject each sentence and runs a meaning check after every rewrite.
Is GPTZero part of Grammarly now?
Superhuman, the company formerly called Grammarly, announced in June 2026 that it agreed to acquire GPTZero. GPTZero is to keep running as a separate product.

RealWrite Editorial Team

The RealWrite editorial team writes about AI detection, editing and how to keep your own voice when you draft with AI. We test what we write about on real drafts before we publish it.

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