GPTZero vs Grammarly (2026): Pricing, Features & Which to Choose

Who comes out ahead

Based only on the facts in our directory. The right pick still depends on the job you need done.

Lower starting price
Grammarly
From $12/mo against from $15/mo
Free plan
Tie
Both have one
Higher rating
Grammarly
4.4 against 4.6
Same job?
Yes
Both are Writing tools

Side by side

Compared on	GPTZero	Grammarly
Our rating	4.4	4.6Better
Starts at	$15/mo	$12/moBetter
Free plan	Yes	Yes
Category	Writing	Writing
Plans	From $15/mo	FreeFree Pro$12/mo Business$15/user/mo
Key features	AI-generated text detection across ChatGPT, Claude, Gemini, and other major LLMs Plagiarism detection bundled alongside AI detection in the same scan Hallucination detection that flags unsupported or fabricated claims in a document Chrome extension for scanning text without leaving the page it appears on API access for institutions screening submissions at scale	Real-time grammar, spelling, and punctuation checks Tone detection and clarity rewrite suggestions GrammarlyGO generative drafting and rewriting Works inline across Gmail, Docs, Slack, and most websites Plagiarism checking on paid tiers
Pros	One of the most established and widely recognized names in AI detection, with a large existing user base Combines AI detection with plagiarism and hallucination checks in a single workflow Free tier is usable for individual, lower-volume checks without a subscription	Free tier is genuinely useful long-term, not just a trial Runs inline almost everywhere you write, no copy-pasting Over a decade of refinement on core grammar detection
Cons	AI detection as a category carries an inherent false-positive risk on any tool, including this one Full-length document scanning beyond the free character limit requires a paid plan Recent acquisition introduces some uncertainty about how the standalone product evolves under Superhuman	Generative features feel bolted onto an older core product Tone and clarity suggestions can be overly conservative Desktop and browser experiences aren't perfectly consistent
Company	GPTZero (Superhuman), founded 2023	Grammarly, founded 2009

Prices come from each vendor's pricing page, last checked 20260731. Check the vendor before you buy.

FAQ

Questions people ask

Is GPTZero better than Grammarly?

In our reviews GPTZero scores 4.4 and Grammarly scores 4.6. The better pick depends on the job. GPTZero: An AI detector built at Princeton that identifies LLM-generated text and now backs Superhuman's authenticity tools. Grammarly: The writing assistant almost everyone has already used.

Which is cheaper, GPTZero or Grammarly?

Grammarly has the lower starting price: from $15/mo for GPTZero and from $12/mo for Grammarly.

Do GPTZero and Grammarly have free plans?

Yes, both have a free plan.

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