Best AI Grammar Checkers 2026
Rankings based on the CORE™ Customer Market Research System.
Reviewed by the Flickthru team · Last updated · How we evaluate
Market Overview
AI grammar checkers catch spelling, grammar and punctuation mistakes as you write and use AI to suggest clearer rewrites and a better tone. We reviewed 17 platforms to arrive at the Top 10 ranked below.
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Quick Reference
- 1GrammarlyFree plan · from $12/mo82.5
- 2LanguageToolFree plan · Premium from about $5.83/mo78.0
- 3ProWritingAidFree plan · from $120/yr74.0
- 4QuillBotFree plan · from $99.95/yr71.0
- 5DeepL WriteFree plan · Write Pro $7.49/user/mo69.5
- 6WordtuneFree plan · from $4.89/mo billed annually68.0
- 7TrinkaFree plan · from $9.99/mo63.5
- 8Hemingway EditorFree web app · Editor Plus $10/mo61.0
- 9Microsoft EditorIncluded with Microsoft 36556.5
- 10GingerFree plan · Premium about $4.99/mo billed annually56.5
Flickthru Score out of 100. Tap a tool to jump to its full review.
Evaluation Methodology
Correction accuracy
How reliably it catches spelling, grammar and punctuation errors without false alarms, and how well it handles style and clarity.
AI rewriting & tone
What its AI does beyond fixing errors: rewriting sentences, changing tone, shortening or expanding text.
Value
What the paid plans give you for their price compared with the other tools here.
Privacy & reliability
How it handles your data and whether customers have been affected by outages or forced plan changes.
Expert & User Ratings
How highly expert reviewers and verified users rate it.
Grammarly
All-round grammar checker
Best For: Anyone who wants accurate, real-time corrections and AI rewrites in almost every app they write in.
Price: Free plan · from $12/mo
Grammarly checks spelling, grammar, punctuation and tone as you type, and offers AI rewrites and tone adjustments. It runs as a browser extension, a desktop app and add-ins for Word and Google Docs, so suggestions appear in most places you write.
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Detailed Analysis
Key features
- Real-time spelling, grammar and punctuation checks
- One-click sentence rewrites and tone adjustments
- Tone detection on the free plan
- Plagiarism and AI-generated text detection on Pro
- Works in browsers, Word, Google Docs and desktop apps
Pricing
- Free: spelling and grammar checks, tone detection and 100 AI prompts
- Pro: $12/month billed annually, or $30/month billed monthly, with 2,000 AI prompts a month
- Enterprise: contact sales for unlimited AI prompts, single sign-on and audit controls
Anyone who wants accurate real-time corrections and AI rewrites across most of the apps they write in.
Month-to-month payers on a tight budget, since the monthly price is much higher than the annual rate.
How it scored
- Correction accuracy: 90/100. Accurate real-time corrections across apps; the benchmark other checkers are compared with.
- AI rewriting & tone: 90/100. Broadest rewriting and tone tools here, with 2,000 AI prompts a month on Pro.
- Value: 60/100. Pro is $12 a month billed annually but $30 month to month.
- Privacy & reliability: 60/100. Scored on a November 2024 global outage that stopped checking and sign-in for several hours.
- Expert & User Ratings: 90/100. Widely recommended by reviewers and used as the benchmark for alternatives.
Our verdict
Grammarly ranks first, pairing accurate real-time corrections with the broadest AI rewriting and tone tools. The main trade-off is the higher monthly price.
- Accurate real-time checking across apps
- 2,000 AI prompts a month on Pro
- Useful free plan
- Pro is $30 a month unless billed annually
- Mostly focused on English
- Best features need Pro
- Pro costs $12 a month only when billed annually; paying month to month is $30.
- The free plan includes 100 AI prompts, while Pro raises that to 2,000 a month.
- Plagiarism and AI-generated text detection are Pro features, and single sign-on and audit controls need an Enterprise quote.
- Price change: Mar 2025: Premium was replaced by Pro at the same price with more AI prompts. Oct 2025: the parent company rebranded as Superhuman; Pro is $12 a month billed annually or $30 monthly, and a Superhuman business bundle costs more.
- Outage: Nov 2024: a global outage stopped text checking, sign-in and editing for several hours before a fix.
LanguageTool
Multilingual grammar checker
Best For: Writers who work in more than one language or want an open-source checker with a clean privacy record.
Price: Free plan · Premium from about $5.83/mo
LanguageTool checks grammar, spelling and style in more than 30 languages through a browser extension, add-ins and a web editor. Its core is open source and can be self-hosted, and it uses AI to offer paraphrasing on top of rule-based checks.
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Detailed Analysis
Key features
- Grammar, spelling and style checks in more than 30 languages
- Open-source core that can be self-hosted
- AI paraphrasing, limited on the free plan
- Picky Mode for stricter style checks on Premium
- Custom style guide and team dictionary on Teams plans
Pricing
- Free: basic checks, 2,000 characters per text field and 3 paraphrases a day
- Premium: up to 150,000 characters per text field, extra checks and unlimited paraphrasing; from about $5.83/month on longer billing terms
- Premium billing options: monthly, quarterly, annual or two-year, with higher month-to-month prices
- Teams: Premium features plus shared style guide and dictionary, priced by team size
Writers who work in several languages or want a lower-cost checker with an open-source core.
Writers who mainly want powerful AI rewriting, which is more limited than at the top-ranked tool.
How it scored
- Correction accuracy: 80/100. Solid rule-based checks in more than 30 languages.
- AI rewriting & tone: 50/100. AI paraphrasing is more limited than the leaders'.
- Value: 90/100. Premium from about $5.83 a month on longer terms with 150,000 characters and unlimited paraphrasing.
- Privacy & reliability: 90/100. Customer inputs are not used to train its models, and the open-source core can be self-hosted.
- Expert & User Ratings: 90/100. Widely recommended by reviewers.
Our verdict
LanguageTool ranks second, covering more than 30 languages at a lower price than the leader. Its AI rewriting is more limited than Grammarly's.
- More than 30 languages
- Open-source core, can be self-hosted
- Lower Premium price on longer terms
- Free plan limits text length and paraphrases
- AI rewriting is less capable than Grammarly's
- Price varies a lot by billing term
- The free plan caps each text field at 2,000 characters and allows 3 paraphrases a day, against 150,000 characters on Premium.
- The from-about-$5.83 a month Premium price applies to longer billing terms; monthly billing costs more.
- Picky Mode is Premium-only, and the shared style guide and team dictionary need a Teams plan priced by team size.
- Outage: No major outage found in news coverage for 2024–2026.
ProWritingAid
Long-form editing suite
Best For: Novelists and long-form writers who want in-depth style reports alongside grammar checks.
Price: Free plan · from $120/yr
ProWritingAid is an editing suite that checks grammar and also produces detailed reports on style, pacing, repetition and readability. It works as a web editor, desktop app and integrations, and is popular with people editing long manuscripts.
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Key features
- More than 20 reports on style, pacing, repetition and readability
- Grammar and spelling checks
- Built for long manuscripts and fiction
- AI Sparks for rewrites, with a daily allowance
- Lifetime licence option
Pricing
- Free: checks 500 words at a time
- Premium: $120/year or $30/month, with 3 AI Sparks a day
- Premium Pro: $144/year, raising AI Sparks to 50 a day
- Lifetime licence: $399
Novelists and long-form writers who want in-depth style reports alongside grammar checks.
Casual writers who want a generous free plan or heavy AI rewriting on a basic tier.
How it scored
- Correction accuracy: 80/100. Solid grammar checking plus more than 20 in-depth style reports.
- AI rewriting & tone: 70/100. AI Sparks rewrites, capped at 3 a day on Premium and 50 on Premium Pro.
- Value: 50/100. Premium rose to $120 a year ($30 monthly) with only 3 AI Sparks a day.
- Privacy & reliability: 70/100. Offers the standard data controls for this type of tool.
- Expert & User Ratings: 90/100. Widely recommended by reviewers.
Our verdict
ProWritingAid ranks third on the strength of its deep editing reports, which suit long manuscripts. Value holds it back after a 2026 price rise.
- More than 20 in-depth reports
- Strong for long manuscripts
- Lifetime licence available
- Annual Premium rose from $79 to $120
- Free plan checks only 500 words
- Premium has just 3 AI Sparks a day
- The free plan checks only 500 words at a time.
- Premium is $120 a year or $30 a month but includes only 3 AI Sparks a day; Premium Pro at $144 a year raises that to 50.
- A lifetime licence is available for $399 if you prefer a one-off payment.
- Price change: 2026: Premium rose from $79 to $120 a year ($30 monthly), a new Premium Pro tier costs $144 a year, and the lifetime licence went from $299 to $399.
- Outage: No major outage found in news coverage for 2024–2026.
QuillBot
Paraphraser and grammar checker
Best For: Students and writers who want a free grammar checker plus strong paraphrasing modes.
Price: Free plan · from $99.95/yr
QuillBot combines a grammar checker with a paraphraser, summariser and citation tools in one account. The grammar checker is free with no word cap, and the paraphraser offers several rewrite modes for changing tone and style.
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Key features
- Free grammar checker with no word cap
- Paraphraser with multiple rewrite and tone modes
- Summariser
- Citation generator
- Browser extension and app integrations
Pricing
- Free: grammar checker with no word cap; paraphrasing capped at 125 words
- Premium: $99.95/year
- Premium month-to-month: $19.95/month
Students and writers who want a free grammar checker plus flexible paraphrasing modes.
Writers who need the most accurate corrections or a low month-to-month price.
How it scored
- Correction accuracy: 70/100. Useful grammar checker, but trails the top three on accuracy.
- AI rewriting & tone: 80/100. Paraphraser with several rewrite and tone modes.
- Value: 80/100. Premium is $99.95 a year for paraphraser, summariser and citations; $19.95 monthly.
- Privacy & reliability: 60/100. Scored on brief unavailability during the December 2025 Cloudflare outage.
- Expert & User Ratings: 60/100. Recommended less often than the leaders.
Our verdict
QuillBot ranks fourth, pairing an uncapped free grammar checker with a multi-mode paraphraser. It trails the top three on correction accuracy.
- Free grammar checker with no word cap
- Several paraphrasing modes
- Summariser and citation tools included
- Free paraphrasing capped at 125 words
- Month-to-month Premium is $19.95
- Trails top three on accuracy
- The grammar checker is free with no word cap, but free paraphrasing stops at 125 words.
- Premium is $99.95 a year, or $19.95 if you pay month to month.
- One account covers the paraphraser, summariser and citation tools.
- Outage: Dec 5, 2025: a Cloudflare outage made QuillBot and other sites unavailable for a short period.
DeepL Write
AI writing and correction tool
Best For: Writers in English and major European languages who want natural corrections and tone options.
Price: Free plan · Write Pro $7.49/user/mo
DeepL Write improves text you paste or type by correcting errors and suggesting more natural phrasing, with tone and style options. Changes are shown as tracked edits so you can accept or reject them.
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Detailed Analysis
Key features
- Natural-sounding corrections and rewrites
- Tone options such as formal, diplomatic and confident
- Changes shown as tracked edits
- Supports English, German, French, Spanish, Italian and Portuguese
- Write Pro adds the fuller feature set
Pricing
- Free version available with core corrections
- Write Pro: $7.49 per user per month, billed annually, as an add-on on individual plans
- Included in DeepL Business and Enterprise plans
Writers in English and major European languages who want natural corrections and tone options.
Writers who need many languages or checking inside every app.
How it scored
- Correction accuracy: 80/100. Natural-sounding corrections shown as tracked edits.
- AI rewriting & tone: 70/100. Useful tone and style options; fuller features need Write Pro.
- Value: 70/100. Write Pro is a $7.49 per user a month add-on billed annually, included in Business plans.
- Privacy & reliability: 70/100. Offers the standard data controls for this type of tool.
- Expert & User Ratings: 40/100. Recommended by fewer reviewers than the leaders.
Our verdict
DeepL Write ranks fifth. Its corrections read naturally and its tone options are useful, but full Write Pro is a paid add-on.
- Natural-sounding corrections
- Tone and style options
- Tracked-edit view of changes
- Write Pro is a paid add-on on individual plans
- Only six languages
- Recommended by fewer reviewers than the leaders
- The free version covers core corrections only; the fuller feature set needs Write Pro.
- On individual plans Write Pro is a separate add-on at $7.49 per user a month, billed annually.
- Write Pro is included in DeepL Business and Enterprise plans, and Write supports only six languages.
- Outage: No major outage found in news coverage for 2024–2026.
Wordtune
AI rewriting assistant
Best For: People who mainly want sentences rewritten in a different tone or length.
Price: Free plan · from $4.89/mo billed annually
Wordtune is an AI rewriting assistant that suggests alternative ways to phrase a sentence, shorten or expand it, or change its tone. It works inside Gmail, Google Docs and other web apps and also includes spelling and grammar checks.
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Detailed Analysis
Key features
- Rewrites that change tone and length
- Unlimited spelling and grammar checks on every plan
- Works in Gmail, Google Docs and other web apps
- AI summarisation of documents
- Vocabulary, clarity and fluency suggestions on Unlimited
Pricing
- Free: 10 rewrites a day and 3 AI summaries a month
- Advanced: $6.99/month, or $4.89/month billed annually, with 30 rewrites a day
- Unlimited: $9.99/month, or $6.99/month billed annually, with unlimited rewrites and summaries
- Paid plans include a 3-day free trial
People who mainly want sentences rewritten in a different tone or length.
Writers who need deep grammar checking as the main feature.
How it scored
- Correction accuracy: 60/100. Includes spelling and grammar checks, but they are secondary to rewriting.
- AI rewriting & tone: 80/100. Natural-sounding rewrites with tone and length changes.
- Value: 80/100. Advanced from $4.89 and Unlimited from $6.99 a month on annual billing.
- Privacy & reliability: 70/100. Offers the standard data controls for this type of tool.
- Expert & User Ratings: 60/100. Recommended less often than the leaders.
Our verdict
Wordtune ranks sixth. Its rewrites sound natural and its price is low, but grammar checking is secondary to rewriting.
- Natural-sounding rewrites
- Works inside Gmail and Google Docs
- Low starting price
- Grammar checking is secondary
- Free plan limits daily rewrites
- Best features need Unlimited
- The free plan allows 10 rewrites a day and 3 AI summaries a month.
- Advanced is $6.99 a month ($4.89 on annual billing) and limits you to 30 rewrites a day; Unlimited is $9.99 a month ($6.99 annually).
- Vocabulary, clarity and fluency suggestions are on Unlimited, and paid plans start with a 3-day free trial.
Trinka
Academic grammar checker
Best For: Researchers and students writing formal academic or technical papers.
Price: Free plan · from $9.99/mo
Trinka is a grammar checker built for academic and technical writing. It checks grammar and formal style and can check against style guides such as APA and IEEE, so it catches formal-writing issues general tools may miss.
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Key features
- Style-guide checks for APA, IEEE, ACS and AGU
- Grammar and formal-writing corrections
- Free plan covering 5,000 words a month
- AI writing requests on Premium
- Confidential Data plan with no storage or AI training on text
Pricing
- Free: 5,000 words a month
- Premium: $9.99/month or $99.90/year, with 25 AI writing requests a month
- Premium Plus: $149.90/year
- Confidential Data: $300/year
Researchers and students writing formal academic or technical papers.
Everyday writers who want heavy AI rewriting or a general-purpose tool.
How it scored
- Correction accuracy: 70/100. Good at formal academic grammar and APA/IEEE style-guide checks; narrower for everyday writing.
- AI rewriting & tone: 40/100. Only 25 AI writing requests a month on Premium.
- Value: 60/100. Premium is $99.90 a year but tightly capped on AI; Confidential Data plan is $300 a year.
- Privacy & reliability: 80/100. Offers a Confidential Data plan with no storage or AI training on text.
- Expert & User Ratings: 70/100. Recommended by several reviewers.
Our verdict
Trinka ranks seventh and is the pick for academic and technical writing thanks to its style-guide checks. It is less useful for everyday writing.
- Academic style-guide checks
- 5,000 free words a month
- Confidential Data plan available
- Only 25 AI requests a month on Premium
- Aimed at academic writing
- Top confidentiality plan is $300 a year
- The free plan covers 5,000 words a month.
- Premium is $9.99 a month or $99.90 a year but includes only 25 AI writing requests a month; Premium Plus is $149.90 a year.
- The Confidential Data plan, which keeps text from being stored or used for AI training, costs $300 a year.
Hemingway Editor
Readability editor
Best For: Writers who want plainer, shorter sentences rather than a full grammar suite.
Price: Free web app · Editor Plus $10/mo
Hemingway Editor highlights long sentences, passive voice and hard-to-read passages so you can simplify your writing. The web app is free, and the paid Editor Plus tier adds AI grammar fixes and rewrites.
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Detailed Analysis
Key features
- Highlights hard-to-read and very hard-to-read sentences
- Readability grade and simple interface
- Flags passive voice and adverbs
- Editor Plus adds AI grammar fixes and rewrites
- Desktop app available
Pricing
- Free: web app with readability highlighting
- Editor Plus: $10/month or $100/year, with AI rewrites drawn from a monthly credit allowance
- Desktop app: $19.99 one-time purchase
Writers who want plainer, shorter sentences rather than a full grammar suite.
Anyone who wants full grammar checking as they type across the web.
How it scored
- Correction accuracy: 50/100. A readability tool first; full grammar checking needs Editor Plus.
- AI rewriting & tone: 50/100. AI grammar fixes and rewrites on Editor Plus, drawn from monthly credits.
- Value: 70/100. Editor Plus is $10 a month or $100 a year; desktop app is a $19.99 one-time purchase.
- Privacy & reliability: 70/100. Offers the standard data controls for this type of tool.
- Expert & User Ratings: 90/100. Widely recommended by reviewers.
Our verdict
Hemingway Editor ranks eighth. It is simple and clear for readability, but fuller grammar checking and AI rewrites need the paid Editor Plus.
- Free web app
- Clear readability feedback
- One-time desktop purchase
- Free version is not a full grammar checker
- AI rewrites use monthly credits
- No browser extension for checking as you type
- The free web app highlights readability but does not do full grammar checking; AI grammar fixes need Editor Plus.
- Editor Plus is $10 a month or $100 a year, and AI rewrites draw on a monthly credit allowance.
- The desktop app is a one-time $19.99 purchase, and there is no browser extension for checking as you type.
Microsoft Editor
Built into Microsoft 365
Best For: Microsoft 365 users who want basic grammar help inside Word, Outlook and Edge at no extra cost.
Price: Included with Microsoft 365
Microsoft Editor is the proofing tool built into Word, Outlook and the Edge browser. It flags spelling, grammar and style issues in many languages, and Microsoft 365 subscribers get additional refinements.
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Key features
- Built into Word, Outlook and Edge
- Spelling and grammar checking in many languages
- Style and clarity suggestions
- Basic checking available without a subscription
- More refinements with a Microsoft 365 plan
Pricing
- Basic checking is free
- Microsoft 365 Personal: $9.99/month since January 2025
- Microsoft 365 Family: $12.99/month since January 2025
- Stronger AI rewrites are handled by Copilot
Microsoft 365 users who want basic grammar help inside Word, Outlook and Edge at no extra cost.
Anyone who wants checking across other browsers and apps or deeper style suggestions.
How it scored
- Correction accuracy: 60/100. Basic checks next to dedicated tools, with weaker style suggestions.
- AI rewriting & tone: 40/100. Stronger AI rewrites are handed off to Copilot.
- Value: 70/100. Refinements come with Microsoft 365 Personal ($9.99) or Family ($12.99), which include the Office apps.
- Privacy & reliability: 50/100. Scored on a several-hour Outlook and Microsoft 365 outage in March 2025 and a January 2025 price rise for existing subscribers.
- Expert & User Ratings: 60/100. Recommended by some reviewers.
Our verdict
Microsoft Editor ranks ninth. It is convenient for Microsoft 365 users, but its checks are basic and its Chrome and Edge extensions were retired in October 2025.
- Built into Word, Outlook and Edge
- No extra cost for Microsoft 365 users
- Supports many languages
- Browser extensions retired Oct 31, 2025
- Weaker style checks than dedicated tools
- Stronger rewrites need Copilot
- Basic checking is free, but extra refinements need a Microsoft 365 plan at $9.99 a month (Personal) or $12.99 a month (Family).
- The browser extensions were retired on 31 October 2025, so Editor now lives in Word, Outlook and Edge.
- Stronger AI rewrites come through Copilot rather than Editor itself.
- Price change: Jan 2025: Microsoft 365 Personal rose from $6.99 to $9.99 a month and Family from $9.99 to $12.99 as Copilot was bundled.
- Outage: Mar 1, 2025: a global Outlook and Microsoft 365 outage disrupted users for several hours.
Ginger
Grammar checker and rephraser
Best For: Budget-minded writers who want sentence rephrasing and translation in a simple checker.
Price: Free plan · Premium about $4.99/mo billed annually
Ginger corrects grammar in context and can rephrase whole sentences. It also includes translation and a practice trainer, which makes it a simple option for beginners and multilingual writers.
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Detailed Analysis
Key features
- Contextual grammar and spelling corrections
- Sentence rephrasing
- Built-in translation
- Personal practice trainer
- Browser and desktop tools
Pricing
- Free plan available with basic checking
- Premium: a 2026 review listed $9.99/month or $4.99/month billed annually, both as discounted rates
- Pricing changes often with promotions; confirm the current price on the vendor's site
Budget-minded writers who want sentence rephrasing and translation in a simple checker.
Writers who need the most thorough corrections or modern AI features.
How it scored
- Correction accuracy: 50/100. Corrections less thorough than newer tools.
- AI rewriting & tone: 50/100. Sentence rephrasing, but AI features trail rivals.
- Value: 70/100. Premium about $4.99 a month billed annually, though prices shift with promotions.
- Privacy & reliability: 70/100. Offers the standard data controls for this type of tool.
- Expert & User Ratings: 60/100. Recommended by some reviewers.
Our verdict
Ginger ranks tenth. Its corrections and AI features lag newer tools, though it remains a low-cost option for beginners and multilingual writers.
- Rephrases sentences in context
- Translation and practice trainer built in
- Low annual price
- Corrections less thorough than newer tools
- AI features trail rivals
- Pricing changes often with promotions
- The free plan offers basic checking only; Premium adds the fuller feature set.
- Premium prices listed were $9.99 a month or $4.99 a month billed annually, both as discounted rates.
- Ginger's pricing shifts often with promotions, so confirm the current price before paying.
Comparison Table
Select products using the Add To Compare buttons above.
How to Choose
Decide what you write most
Everyday email and web writing, long manuscripts, academic papers and multilingual text each suit different tools. General checkers such as Grammarly cover most situations, while ProWritingAid, Trinka and LanguageTool are stronger for specific jobs. Pick the tool that matches your main use rather than the longest feature list.
Check where it works
Some checkers run in browsers, Word, Google Docs and desktop apps, while others are web editors you paste text into. Confirm the tool works in the apps you actually use, and note that Microsoft Editor's Chrome and Edge extensions were retired on October 31, 2025.
Separate checking from rewriting
Grammar and spelling checks are often free, but AI rewrites, tone changes and paraphrasing are usually metered or paid. Look at daily or monthly limits, such as prompts, Sparks or credits, before you assume a plan is unlimited.
Compare monthly and annual prices
Many tools advertise the annual rate, and month-to-month billing can cost two or three times as much. Grammarly Pro is $12 a month billed annually against $30 monthly, so check which billing term the headline price refers to.
Consider language support
If you write in more than English, compare language coverage. LanguageTool checks more than 30 languages, while DeepL Write covers six major European languages. Some tools are English only, so test a sample in each language you need.
Try the free plan on your own text
Paste a real draft into two or three free plans and compare what each flags and how natural the suggestions sound. Free plans differ in word or character caps, so make sure the limit fits your typical document length.
Frequently Asked Questions
Is there a good free grammar checker?
Yes. Grammarly, LanguageTool, QuillBot and Wordtune all have free plans that check spelling and grammar, and Hemingway Editor's web app is free for readability. Free plans usually cap AI rewrites or text length, so check the limits.
Which grammar checker is best for long manuscripts?
ProWritingAid is built for long-form writing, with more than 20 reports on style, pacing, repetition and readability. Its free plan checks only 500 words at a time, so novelists usually need a paid plan or the lifetime licence.
Which tool is best for academic writing?
Trinka is aimed at academic and technical papers and checks against style guides such as APA and IEEE. Its free plan covers 5,000 words a month, and Premium is $99.90 a year.
Can a grammar checker work in several languages?
LanguageTool supports more than 30 languages, which is the widest coverage on this page. DeepL Write covers English, German, French, Spanish, Italian and Portuguese, and Grammarly focuses on English.
Do I still need a grammar checker if I have Microsoft 365?
Microsoft Editor is built into Word, Outlook and Edge and is enough for basic checks. Writers who want stronger style suggestions, AI rewrites or checking in other apps usually add a dedicated tool such as Grammarly or LanguageTool.
How We Evaluated
Every Flickthru ranking follows the same five-step process, applied the same way to every product on the page.
- Market scan: We gathered the 17 platforms recommended across current expert reviews, buyer guides and verified-user ratings, then shortlisted the 10 that best fit this category and offer their own built-in AI.
- Evidence gathering: For each shortlisted product we collected features, plans and current pricing from the vendor, alongside the strengths and weaknesses reported in recent expert reviews.
- Risk checks: We checked every product for recent price changes and service reliability. Anything relevant is summarised in the product’s Detailed Analysis and reflected in its score.
- Scoring: Each product is scored against the five criteria in our Evaluation Methodology using the same rules for every product, and the Flickthru Score out of 100 combines them. Correction accuracy, the main job these tools do, counts most. Value is judged on what the paid plans deliver for their price. Each product’s Detailed Analysis explains how it scored on every criterion.
- Editorial independence: Rankings are decided by Flickthru’s editorial process alone. Placement cannot be bought.
This ranking was last updated in September 2026.