Neither one wins outright. LanguageTool takes price, privacy and multilingual support: it costs a fraction of Grammarly, supports more than 30 languages, and is the only one of the two you can host on your own machine. Grammarly takes depth: its English analysis, tone suggestions and rewrites are more sophisticated than anything LanguageTool offers. Which one wins on your Mac comes down to whether you want breadth and control, or one language handled thoroughly. The table below adds a third option, Charm, which corrects English inline as you type, on-device, for $9.99 once rather than a subscription.
What is the core difference between Grammarly and LanguageTool?
Grammarly is an English writing coach. LanguageTool is a multilingual proofreader. That single distinction explains almost every other difference between them, including price, privacy posture and the kind of feedback you get on a sentence.
Grammarly reads your writing and comments on it. Alongside spelling and grammar it flags tone, wordiness, passive constructions and clarity, then offers full-sentence rewrites. The paid tiers lean heavily on generative AI, so it behaves less like a spell checker and more like an editor with opinions about your voice.
LanguageTool stays closer to proofreading. Its large rule set, plus statistical and AI-assisted checks, is applied across dozens of languages rather than going deep on one. It will catch a subject-verb disagreement or a wrong preposition, but it will not tell you that your paragraph sounds unconfident.
Scribbr's editorial head-to-head lands in the same place: comparable on mechanics, different on everything above them.
Which is more accurate?
On plain errors, they are close. Both catch typos, misused homophones, missing commas and broken agreement well enough that most writers will not see daylight between them. The gap appears above that layer: Grammarly flags more issues per document because it counts style, tone and clarity as issues.
That sensitivity cuts both ways. Grammarly produces more suggestions you will want to dismiss, especially on technical writing, and it is often accused of pushing everything toward the same neutral corporate register. LanguageTool is quieter: fewer false alarms, but fewer genuine catches on awkward phrasing.
Review data on G2's side-by-side comparison reflects that split, with users rating Grammarly higher on suggestion quality and LanguageTool higher on value. If you want a broader view of the category, our guide to grammar checkers on Mac covers the other contenders.
Is LanguageTool more private than Grammarly?
Yes, and it is not close. Both send your text to their servers by default, so on a standard setup you are trusting a company with everything you type. The difference is that LanguageTool publishes an open-source server you can run yourself, on your own Mac or inside your company network. Grammarly has no equivalent.
For casual writing the default cloud setup is a reasonable trade. For work under NDA, legal drafting or unreleased product copy it is a real problem, and self-hosting is the only way to remove it. Running your own instance is not a one-click job, but it is documented and free.
We go into Grammarly's data handling in more detail in our piece on whether Grammarly is safe on a Mac. The short version: it is not reckless, but the text does leave your machine.
Which is better value?
LanguageTool, by a wide margin. Its Premium tier sits at roughly €60 a year, around €5 a month on annual billing, with month-to-month closer to €20. Grammarly Pro is around $12 a month billed annually and noticeably more on shorter terms, so you are looking at roughly double the annual cost.
Both free tiers are worth taking seriously, though LanguageTool's is the stronger one: it handles spelling, punctuation and basic grammar, while Grammarly's free version holds back the tone, clarity and rewrite features that are the main reason to pick Grammarly at all.
Both paid plans recur: roughly $144 a year for Grammarly Pro, roughly €60 a year for LanguageTool Premium, every year. Charm is $9.99 once for up to 3 Macs, less than a single year of either. That contrast is with the paid tiers only; LanguageTool's free tier still costs nothing.
| Feature | Grammarly | LanguageTool | Charm |
|---|---|---|---|
| Languages supported | English only | 30+ languages and dialects | English only |
| Spelling and grammar | Strong | Strong | Strong on spelling; grammar limited to mechanics |
| Tone and clarity suggestions | Yes, its main strength | Limited style rules only | No, it never rewords you |
| AI rewriting | Yes, on paid tiers | Basic paraphrasing | No |
| How corrections reach you | Underlines you click | Underlines you click | Inline as you type in native Mac apps; Fix Selection (Option-Command-V) in browsers and Electron apps |
| Self-hosting | No | Yes, open-source server | Not needed, runs on your Mac |
| Free tier | Correctness only | Usable, with text limits | None, paid only |
| Typical paid price | Around $12/month annually, roughly $144 a year | Around €5/month annually, roughly €60 a year | $9.99 once for up to 3 Macs, no subscription |
| Text sent to servers | Yes | Yes, unless self-hosted | No, fully on-device |
Which is better for languages other than English?
LanguageTool wins by default, because Grammarly does not compete. Grammarly checks English and nothing else. LanguageTool covers more than 30 languages and dialects, including German, French, Spanish, Portuguese, Dutch and Polish, and it handles regional variants within them.
This matters more than it first appears. If you write English at work and another language at home, one LanguageTool subscription covers both; with Grammarly you would need a second tool anyway.
How well does each work across Mac apps?
Both work the same way on macOS: a browser extension covering Gmail, Google Docs and most web text fields, plus a desktop app that overlays native apps.
Neither integrates cleanly everywhere. Terminal, IDEs and many Electron apps end up unsupported or awkward, and underlines can drift out of position in editors with unusual text layout. If you mostly write in a browser, both are fine. If you write everywhere on your Mac, both leave gaps.
Which should you choose?
Choose Grammarly if you write in English only, care about tone as much as correctness, and are happy paying a premium for deeper analysis. It is the better coach.
Choose LanguageTool if you want a solid checker at half the price, write in more than one language, or need self-hosting for confidentiality. It is also the better free option. A useful detail worth knowing: Grammarly's parent company rebranded to Superhuman in October 2025 and now sells a wider AI assistant, so expect the product to keep expanding beyond writing.
A third option if you want corrections applied as you type
Neither tool fixes your text automatically as you type. Both are cloud checkers by default that underline problems for you to click.
That is what Charm does: it corrects spelling and mechanics and predicts your next word inline in every native Mac app, on-device, with no account and no internet needed. It is English only, it fixes mechanics without rewording your voice, and it does not attempt Grammarly's depth of style analysis. For the direct comparisons, see Charm vs Grammarly, Charm vs LanguageTool and our roundup of LanguageTool alternatives for Mac.
Frequently asked questions
Is LanguageTool as good as Grammarly?
On spelling, punctuation and standard English grammar, LanguageTool is close enough that most writers will not notice a gap. Grammarly pulls ahead on tone, clarity and full-sentence rewrites. If you want an editor that reshapes your prose, Grammarly is stronger. If you want a corrector that catches mistakes, LanguageTool does it for far less.
Is LanguageTool free?
LanguageTool has a genuinely usable free tier covering spelling, punctuation and basic grammar, with a limit on how much text you can check at once. Premium unlocks the advanced style rules and longer limits. There is also an open-source server you can run yourself at no cost.
Is Grammarly still called Grammarly?
The company rebranded to Superhuman in October 2025 after acquiring the email app of that name, and now sells a broader AI assistant under that banner. The writing product is still marketed and installed as Grammarly on a Mac, so the tool has not changed name even though the company has.
Which is safer for confidential writing?
LanguageTool, because it can be self-hosted. Both send your text to their servers by default, a problem for anyone handling client work, legal drafts or unreleased code. LanguageTool's server is open source and can run on your own machine, so the text never leaves infrastructure you control. Grammarly offers no equivalent.
Can you run LanguageTool and Grammarly at the same time on a Mac?
Technically yes, but we do not recommend it. Both install browser extensions and both underline suggestions in the same text fields, so they fight over the same space and produce duplicated or contradictory flags. Pick one and disable the other's extension.