Grammarly is the strongest all-around pick for most people, and it's not close: broadest platform coverage, the biggest AI-prompt allowance, and a free tier that actually catches real mistakes. If you just want something cheap and solid without shopping five options, LanguageTool is the more budget-friendly default, especially with its two-year plan.
Proofreading tools stopped being simple spell-checkers years ago. The seven below now bundle grammar, style, tone, paraphrasing, and AI-detection into one subscription, and a couple even ship their own MCP servers so an AI assistant can call them directly.
We priced every plan from each vendor's own pricing page, checked for an official MCP server versus community wrappers, and confirmed API access from primary developer docs rather than a features list.
Quick take: Grammarly, ProWritingAid, LanguageTool, QuillBot, Sapling, Wordtune, and Trinka AI are the seven proofreading tools compared here on pricing, AI features, MCP support, and API access. Best overall: Grammarly. Best budget pick: LanguageTool.
Last updated: August 16, 2026
Editorial disclosure: PickMySoft may earn a commission from some links on this page; our reviews and rankings are independent.
Why You Need Proofreading Software
- Typos cost more than they look like they should. A single grammar slip in a client email or job application can undercut a message before anyone reads past the first line.
- Tone-checking catches what spell-check can't. Modern tools flag when a message reads as blunt or overly casual for the audience, not just when a word is misspelled.
- AI-detection is now a proofreading feature, not a separate tool. Students and content teams increasingly need to confirm writing reads as human-authored before submission.
- Paraphrasing and rewriting save real editing time. A rewrite suggestion that preserves meaning while fixing awkward phrasing beats manually rewording a paragraph three times.
- API and MCP access matter if you're building on top of it. Teams embedding grammar checking into their own product need a documented API, not just a browser extension.
How We Evaluated
We scored each tool on five factors: pricing transparency and value across tiers, breadth and quality of AI writing features, official MCP support (first-party versus community-built), API/SDK depth for developers, and platform coverage across browsers, apps, and word processors.
Every price below comes from each vendor's own pricing page. Where a vendor's plan pricing wasn't displayed in static page content, we said so rather than guessing.
Best 7 Proofreading Software in 2026
1. Grammarly
Grammarly is the name most people already have installed, and the reason is simple: it works everywhere you type, from Gmail to Slack to a Word doc, without you thinking about it.
Pricing: Free ($0, 100 AI prompts/month); Pro $12/month with 2,000 AI prompts/member/month; Enterprise custom pricing with unlimited prompts, BYOK encryption, and data loss prevention.
Top features:
- Full-sentence AI rewrites and tone adjustment
- Plagiarism and AI-generated text detection on Pro
- Works across browser, desktop, mobile, and Office/Google Docs
- English fluency assistance for non-native writers
- Proactive suggestions tuned to audience and intent
- Enterprise-grade DLP and custom roles on top tier
Pros:
- Broadest platform coverage of any tool in this list
- Free tier is genuinely usable, not just a trial
- Enterprise tier adds real security controls (BYOK, DLP)
Cons:
- Enterprise pricing is fully opaque — sales call required
- AI-prompt caps on Free and Pro limit heavy rewriting use
AI/MCP Integration: Community/third-party only — several unofficial MCP servers exist on GitHub and MCP directories, but no MCP server built and maintained by Grammarly itself was found as of this writing.
API Integration: Not clearly documented as of this writing — Grammarly doesn't publish a general developer API page; integration is primarily through its own apps and browser extension.
Cloud Based: Yes — cloud-hosted, with desktop apps that sync to the same account.
Platforms: Browser extension, Windows and Mac apps, iOS and Android, Microsoft Word, Google Docs, and Slack.
Best for: anyone who wants one tool that just works across every app they already use.
Editor score: 4.6/5 — the most complete everyday tool here, docked for opaque Enterprise pricing and no official MCP server.
2. ProWritingAid
ProWritingAid is built for people editing something long — a novel, a thesis, a report — with 25+ analysis reports most competitors don't attempt.
Pricing: Free (500-word limit, 2 reports/day); Premium $30/month or $120/year ($10/month equivalent) or $399 lifetime; Premium Pro $36/month or $144/year or $699 lifetime, adding live workshops and expert critiques.
Top features:
- 25+ in-depth writing analysis reports
- Sparks AI rewriting tool for style and clarity
- Chapter Critique for long-form manuscripts
- Official JavaScript, TypeScript, and PHP SDKs
- Terminology and plagiarism checking built in
- Lifetime license option, rare among competitors
Pros:
- Deepest style and structure analysis of any tool here
- Official SDKs make it the most developer-friendly non-MCP option
- Lifetime pricing avoids ongoing subscription cost
Cons:
- Most expensive monthly plan in this comparison
- Free tier's 500-word limit is too restrictive for real editing
AI/MCP Integration: Not documented as of this writing — no MCP server, official or community, was found for ProWritingAid.
API Integration: Yes — official JavaScript, TypeScript, and PHP SDKs are published and maintained on ProWritingAid's own GitHub organization.
Cloud Based: Yes — cloud-hosted with browser, desktop, and add-in access.
Platforms: Browser extension, Windows and Mac desktop apps, Microsoft Word and Google Docs add-ins, Scrivener.
Best for: authors, students, and anyone editing long manuscripts who wants deep structural feedback, not just grammar.
Editor score: 4.2/5 — unmatched depth for long-form editing, held back by the highest price of the seven and no MCP path.
3. LanguageTool
LanguageTool's open-source roots show in its pricing and its API: it's the cheapest capable option here over a multi-year commitment, and it's the one built API-first from the start.
Pricing: Free (2,000-character limit, 3 AI paraphrases/day); Premium €19.90/month, €13.30/month quarterly, €4.90/month annual, or €4.16/month on a 2-year plan; Teams €56.90/user/year.
Top features:
- Documented HTTP/REST Proofreading API with Swagger docs
- Support for 25+ languages and regional variants
- Personal and Team Style Guides for consistent voice
- Unlimited AI-powered sentence paraphrasing on Premium
- Picky Mode for stricter style enforcement
- Self-hostable open-source core (separate from the hosted product)
Pros:
- Cheapest long-term pricing of any capable tool in this list
- Real, documented HTTP API built for developers from day one
- Open-source core gives self-hosting flexibility others don't
Cons:
- No MCP support, official or community, found as of this writing
- Monthly (non-annual) pricing is the priciest tier-for-tier in this list
AI/MCP Integration: Not documented as of this writing — no MCP server was found in LanguageTool's official documentation.
API Integration: Yes — a fully documented HTTP/REST Proofreading API with Swagger-based reference docs.
Cloud Based: Yes — hosted service, with an open-source core available for self-hosting separately.
Platforms: Browser extension, Windows and Mac apps, Microsoft Word and Google Docs add-ins, mobile keyboards.
Best for: budget-conscious users and developers who want a real API without Grammarly's opacity.
Editor score: 4.3/5 — the best long-term value and the most genuinely developer-friendly API here, docked for having no MCP path at all.
4. QuillBot
QuillBot built its reputation on paraphrasing before grammar checking, and that ordering still shows: nine rewrite modes is more variety than any other tool here offers.
Pricing: Free ($0, limited daily use); Premium $8.33/month billed annually; Team pricing not published on the site as of this writing.
Top features:
- Nine distinct paraphrasing modes
- Built-in AI Detector and AI Humanizer
- Summarization tool for condensing long text
- AI Chat with expanded usage on Premium
- AI image generation bundled into Premium (300/month)
- Browser, Word, and mobile app coverage
Pros:
- Cheapest capable paid tier of the seven at $8.33/month
- Widest range of paraphrasing styles and tones
- Bundles detection, humanizing, and summarization in one plan
Cons:
- No official developer API found as of this writing
- Team plan pricing isn't published — requires contacting sales to compare
AI/MCP Integration: Not documented as of this writing — no official or community MCP server was found for QuillBot.
API Integration: Not documented as of this writing — QuillBot doesn't publish a general developer API.
Cloud Based: Yes — cloud-hosted, browser and app-based.
Platforms: Browser extension (Chrome, Edge, Safari), Microsoft Word, mobile apps.
Best for: writers who paraphrase and rewrite constantly and want the cheapest capable plan here.
Editor score: 4.0/5 — genuinely strong paraphrasing at a low price, but the weakest developer story of the seven.
5. Sapling
Sapling is the outlier here in the best way: it ships a dedicated, official MCP Server as its own product, not a bolted-on afterthought — the strongest MCP story in this whole category.
Pricing: Free ($0, 20 snippets); Pro $25/month or $12/month billed annually; Enterprise from $15/seat/month (10-seat minimum) with self-hosted and custom integration options; API plan usage-based with a $5 one-time minimum.
Top features:
- Dedicated, official MCP Server product
- Usage-based API plan built for developers
- Autocomplete Everywhere across web apps
- Self-hosted deployment option on Enterprise
- Team analytics and domain-level administration
- Single Sign-On and SCIM support on Enterprise
Pros:
- Only tool in this list with an official, dedicated MCP Server
- Usage-based API pricing scales down to small projects
- Self-hosting option matters for security-sensitive teams
Cons:
- Smaller mainstream/consumer footprint than Grammarly or QuillBot
- Enterprise minimum of 10 seats prices out very small teams
AI/MCP Integration: Yes — official. Sapling publishes a dedicated MCP Server product with its own documentation at sapling.ai/mcp.
API Integration: Yes — a usage-based developer API with a documented pricing plan, separate from the consumer subscription tiers.
Cloud Based: Yes — cloud-hosted, with a self-hosted deployment option on Enterprise.
Platforms: Browser extension, web apps via Autocomplete Everywhere, API, and MCP Server.
Best for: developers and teams that want to wire proofreading directly into an AI assistant or their own product.
Editor score: 4.4/5 — the clear MCP leader in this category, with real API pricing to match; smaller brand recognition than the top two.
6. Wordtune
Wordtune's whole interface is built around one motion: highlight a sentence, get a better version. It's the simplest tool here, and the cheapest entry point into a paid plan.
Pricing: Basic free (10 rewrites/day, 3 AI summaries/month); Advanced $6.99/month or $4.89/month annual; Unlimited $9.99/month or $6.99/month annual.
Top features:
- One-click sentence rewrites tuned for clarity and tone
- AI summarization for condensing long passages
- Vocabulary and fluency enhancement suggestions
- AI content humanization tool
- Unlimited rewrites on the top tier
- Browser and mobile keyboard integration
Pros:
- Cheapest entry-level paid plan of any tool in this list
- Simplest interface — genuinely fast to learn
- Unlimited tier is affordable relative to competitors
Cons:
- No documented API or MCP support of any kind found
- Fewer deep-editing features than ProWritingAid or Trinka
AI/MCP Integration: Not documented as of this writing — no MCP server, official or community, was found for Wordtune.
API Integration: Not documented as of this writing — no general developer API is published on Wordtune's site.
Cloud Based: Yes — cloud-hosted, browser and app-based.
Platforms: Browser extension, iOS and Android keyboards, Microsoft Word and Google Docs integration.
Best for: writers who want fast, simple rewrite suggestions without a steep learning curve.
Editor score: 3.9/5 — the easiest tool to pick up here, but the weakest technical and developer story of the seven.
7. Trinka AI
Trinka is built specifically for academic and technical writing, with style-guide support (APA, IEEE, ACS, AGU) none of the general-purpose tools here even attempt.
Pricing: Basic free (5,000 words/month, 5 AI requests/month); Premium and Premium Plus pricing wasn't displayed in static page content as of this writing; Confidential Data tier $300/year ($41.67/month equivalent) with real-time data deletion and SOC2/HIPAA/GDPR compliance; Enterprise and Institutional plans are custom-quoted.
Top features:
- Academic style guides: APA, IEEE, ACS, AGU
- Technical and subject-specific grammar checking
- AI detector rated #1 on the RAID Leaderboard per Trinka
- Grammar Checker API and SDK for developers
- On-premise deployment for institutions
- LMS integration with Canvas, Moodle, Blackboard, D2L
Pros:
- Only tool here built specifically for academic/technical writing
- Real API and SDK for institutional integration
- Confidential Data tier is a genuine compliance-grade option
Cons:
- Premium and Premium Plus pricing isn't published in static page content
- No MCP support, official or community, found as of this writing
AI/MCP Integration: Not documented as of this writing — no MCP server was found in Trinka's developer documentation.
API Integration: Yes — a Grammar Checker API and SDK are documented through Trinka's developer portal, alongside on-premise deployment options.
Cloud Based: Yes — cloud-hosted by default, with on-premise deployment available for institutions.
Platforms: Browser extension, Microsoft Word add-in, offline desktop app on the Confidential Data tier, LMS integrations.
Best for: academic writers, researchers, and institutions that need subject-specific style checking and real compliance controls.
Editor score: 4.1/5 — the strongest academic/technical fit here, held back by unpublished mid-tier pricing and no MCP path.
Comparison Table
| Tool | Best For | Starting Price | Standout Feature | AI-MCP Support | API Integration |
|---|---|---|---|---|---|
| Grammarly | All-around everyday use | Free / $12/mo (Pro) | Works everywhere you already type | Community only | Not documented |
| ProWritingAid | Long-form manuscripts | Free / $10/mo (Premium, annual) | 25+ in-depth writing reports | Not documented | Yes — official SDKs |
| LanguageTool | Budget-conscious & developers | Free / €4.16/mo (2-yr Premium) | Documented HTTP Proofreading API | Not documented | Yes — REST API |
| QuillBot | Heavy paraphrasing | Free / $8.33/mo (annual) | 9 paraphrasing modes | Not documented | Not documented |
| Sapling | Developers & AI integration | Free / $12/mo (Pro, annual) | Official, dedicated MCP Server | Official (first-party) | Yes — usage-based API |
| Wordtune | Fast, simple rewrites | Free / $4.89/mo (Advanced, annual) | One-click sentence rewrites | Not documented | Not documented |
| Trinka AI | Academic & technical writing | Free / custom (Premium) | APA/IEEE/ACS/AGU style guides | Not documented | Yes — Grammar Checker API |
How to Choose Proofreading Software
- Match the tool to what you're actually writing. Long manuscripts need ProWritingAid-level structural feedback; quick emails don't.
- Check whether you need an API or MCP server before committing. Sapling and LanguageTool are the only two with a real developer story here.
- Compare annual pricing, not just the monthly rate. Several tools here cut their effective price by 40-60% on annual or multi-year plans.
- Confirm platform coverage matches your workflow. A tool that doesn't support your word processor or CMS isn't worth the subscription.
- If academic or technical writing is the use case, prioritize style-guide support over general polish.
What This Actually Costs: A Worked Example
For a 5-person content team needing daily proofreading: Grammarly Pro at $12/month/seat runs $60/month. LanguageTool Premium on its annual plan runs closer to €24.50/month total (roughly $26 at typical exchange rates) for the same headcount. QuillBot Premium at $8.33/month/seat lands at about $42/month. The gap between the cheapest and most expensive realistic option here is roughly 2-3x for the same five seats — worth checking before defaulting to the best-known name.
Final Thoughts
Want one tool that works everywhere without a second thought? Grammarly. Editing something long and want real structural feedback? ProWritingAid. Building proofreading into your own product or an AI assistant? Sapling is the only one here that takes that seriously.
Tight budget and don't need the extras? LanguageTool's multi-year plan is hard to beat. Academic or technical writing with real compliance needs? Trinka. Just want fast rewrites without learning a new interface? Wordtune gets you there in minutes.