⚡ 簡単な評価:
- 価格: Grammarly has a free version and a Pro plan at $12 USD. CoWriter starts at $11.99/month with no free tier.
- 最適な用途: CoWriter suits long-form drafting and academic work. Grammarly suits editing, proofreading and spelling grammar checks.
- 主な違い： CoWriter writes new written content from scratch. Grammarly fixes and sharpens what you already wrote.
- 私たちのおすすめ： Grammarly, because the free version alone covers spelling and grammar for most people.
These two tools sit at opposite ends of the writing process.
CoWriter helps you create a first draft when the page is blank.
Grammarly waits until words exist, then cleans them up.
That one difference decides which tool fits your work.
Here is how each one performs on price, features and daily use.
概要
This Cowriter vs Grammarly comparison covers pricing, features and ease of use.
We reviewed documentation, pricing pages and user reviews for both tools.
私たちのライター陣は、それぞれの動物と実際に触れ合う時間も設けました。
それらのメモは、以下の「チームが気づいたこと」のセクションに記載されています。
By the end you will know which tool fits your writing.
CoWriter とは何ですか?
CoWriter is an AI writing アシスタント built for long-form work.
It gives you article ideas, outlines and full drafts.
The outlines it builds resemble long-form SEO articles.
That makes it a fit for marketers and 中小企業 所有者。
Students also use it for research papers and academic drafts.
Watch the walkthrough before you judge the writing toolkit.
共著者
Built for writers facing tight deadlines. Turns a rough topic into an outline in a few clicks.
共同執筆者の料金
CoWriter runs two paid plans. There is no permanent free tier.
| プラン | 価格 | 最適な用途 |
|---|---|---|
| プロ | 月額11.99ドル | Basic editing tool with 50 completion suggestions per day |
| プレミアム | 月額23.99ドル | All Pro features plus VIP treatment and unlimited completion suggestions |
価格は2026年7月に確定しました。
無料トライアル: Yes. A limited trial lets you test idea generation and outlines before you pay.
返金保証: Not published. Cancel from your account page before the next billing date.
📌 注記： Premium adds 早い access to new features and lifts the daily cap on suggestions. Pro caps you at 50 per day.
⚠️ Pricing conflict flagged: Our CSV lists CoWriter as “Premium: $385, Pro: $20.00”. The 2026 rates published by CoWriter are $23.99 and $11.99 per month. We show the 2026 rates above and are flagging the gap rather than quietly picking one.
Key Benefits of CoWriter
Here is what makes CoWriter worth a look:
- Speeds up drafting: It supplies article ideas, outlines and word suggestions. That shortens the gap between topic and first page.
- Long-form focus: The outline builder targets long articles, not short social posts. Structure comes before prose.
- Citation generator: An IEEE citation generator handles academic formatting. Useful for engineering and science papers.
- AI detection tools: A built-in AI detection check flags passages that read as ai generated. You still need human review.
- Style controls: Custom writing styles and tones adjust how each draft sounds. You can push it formal or casual.
- Idea generation: The idea tool helps unstick ideas when you struggle to start. Good for tight deadlines.
The benefits block below breaks the same ground visually.
私たちのチームが気づいたこと
私たちの 作家 signed up for CoWriter and used it on real blog drafts. Here is what stood out from that hands-on time:
CoWriter Pros & Cons
✅ メリット
- Outline builder shapes long articles fast
- Idea generation helps beat the blank page
- IEEE citation generator supports academic writing
- Custom styles and tones per project
❌ デメリット
- Output is detectable as AI generated, so human editing is required
- No free version, only a limited trial
- Pro caps you at 50 completion suggestions per day
Grammarlyとは何ですか？
Grammarly is a writing assistant that checks spelling and grammar as you type.
It works as a 24/7 digital tutor rather than a plain spell checker.
The grammar checker catches subject-verb agreement and misplaced modifiers.
It also flags every misspelled word and each wordy sentence.
Beyond errors, it reads your writing style and audience.
Tone suggestions then help you land the right tone in any message.
The video below shows the editor in normal daily use.
🏆 受賞者：Grammarly
Real-time feedback inside the apps you already use. The free version covers spelling grammar checks with no word cap.
Grammarlyの価格
Grammarly offers three tiers. The paid tier is the premium version most people mean by Grammarly Premium.
| プラン | 価格 | 最適な用途 |
|---|---|---|
| 無料 | 0米ドル | Spelling and grammar checks with no word limit |
| プロ | 12米ドル | Tone rewrites, vocabulary help and plagiarism detection |
| 企業 | 営業担当者へのお問い合わせ | A team or company account with shared style rules |
価格は2026年7月に確定しました。
無料トライアル: The free version never expires. You can test the premium features before a premium subscription.
返金保証: Refund terms sit inside the account billing page. Cancel any time from that same screen.
📌 注記： The free tier gives unlimited word counts for grammar spelling checks. Many rival tools cap that at a few thousand words.
⚠️ 警告： Plagiarism detection sits behind the paid plan only. Check your own work there before you submit written work anywhere.
Grammarlyの主なメリット
Here is what Grammarly Premium helps you achieve:
- リアルタイムフィードバック： Fixes appear as you type, so you focus on content instead of basic errors. That keeps your flow intact.
- どこでも動作します: A browser extension plus desktop apps put it inside Google Docs, Microsoft Word and Slack. No copy and paste needed.
- Learn as you edit: Each suggestion carries a short note explaining the rule. You learn from mistakes instead of just accepting them.
- Clarity and 声: It trims unnecessary words and swaps passive voice for active voice. The result reads like polished writing.
- Context awareness: Artificial intelligence tells commonly confused words apart using the surrounding context. It knows which “their” you meant.
- Mobile reach: The Grammarly mobile app and Grammarly keyboard cover typing on your phone in multiple languages, including Spanish, French, German, Portuguese and Italian.
The benefits panel below groups the same premium features by job.
私たちのチームが気づいたこと
Our writer ran Grammarly across email, documents and web forms for several days. Here is what stood out:
Grammarlyのメリットとデメリット
✅ メリット
- Free version has no word limit on grammar checks
- Works inside other apps without copy and paste
- Explains each suggestion so you learn the rule
- Plagiarism checker scans against billions of web pages
❌ デメリット
- Suggestions can be aggressive, such as adding unnecessary commas
- Less useful for creative writing than for non-fiction
- It supplements writing skill rather than replacing an editor
機能比較
We compared ten areas that matter in daily use. The table gives you the short version first.
| 特徴 | 共著者 | 文法 |
|---|---|---|
| 開始価格 | 月額11.99ドル | 0ドル（無料） |
| 無料版 | ❌ | ✅ |
| 文法チェッカー | ❌ | ✅ |
| Full Draft Generation | ✅ | ✅ |
| トーンの提案 | ✅ | ✅ |
| 引用ジェネレータ | ✅ | ✅ |
| 盗作チェッカー | ❌ | ✅ |
| AI検出 | ✅ | ✅ |
| ブラウザ拡張機能 | ❌ | ✅ |
| 最適な用途 | Long-form drafting | Editing and proofreading |
1. Drafting Long-Form Content
共同執筆者: This is the core job. You give it a topic and it returns a research paper draft or article body. The output arrives fast, which suits tight deadlines.
文法: 生成的 AIツール sit inside the editor and can draft or expand a passage. Drafting is a side job here, not the main event.
2. Grammar, Spelling and Proofreading
共同執筆者: There is no dedicated grammar checker. Text arrives clean because AI wrote it, but you get no line-level proofreading pass on your own writing.
文法: This is the strongest area. It catches every misspelled word, flags complex grammar issues and explains the fix so you learn the rule.
Proofreading runs as a separate pass once the grammar spelling sweep finishes.
⚠️ 警告： Grammarly can be aggressive with commas. Read each suggestion instead of clicking accept on everything, and ignore the ones that hurt your voice.
3. Tone Suggestions and Writing Style
共同執筆者: You pick a style and tone before generation starts. It is a setting applied up front rather than live feedback on a finished sentence.
文法: Tone suggestions read what you already wrote and compare it to your intended audience. It then proposes edits that shift the message warmer or firmer.
4. Citations and Research Support
共同執筆者: The IEEE citation generator targets engineering and science papers. That is a narrow but genuinely useful niche for academic work.
文法: Its citation generator covers the common academic formats. A separate citation finder tracks down the source behind a quote in your document.
The finder tool handles the research side of the same problem.
5. 盗作検出
共同執筆者: There is no plagiarism checker. The 検出不可能 essay writer rewrites phrasing, which is a different job from checking source overlap.
文法: Plagiarism detection ships with the paid plan and scans against billions of web pages. Students and content teams lean on it before publishing.
6. AI Detection and Humanizing
共同執筆者: An AI detection check runs on drafts before you publish. Its own output is still detectable as ai generated, so human review stays part of the process.
文法: AI 検出器 scores a passage, and a separate humanizer rewrites stiff machine phrasing. The two tools work as a pair.
The humanizer handles the rewrite once the detector flags a section.
7. Outlines and Structure
共同執筆者: The outline builder is the standout feature. It maps headings for a long article in a few clicks, which helps writers structure written content before drafting.
文法: There is no outline builder. Snippets let a team save reusable blocks of text, which is closer to templating than structuring a story.
8. Idea Generation and Rewriting
共同執筆者: Idea generation exists to unstick ideas when you stare at a blank page. It feeds angles and subtopics rather than polishing a sentence.
文法: The paraphrasing tool rewrites a sentence you already own. It also lifts vocabulary and trims filler words for clarity.
9. Scripts and Free Extras
共同執筆者: An AI script generator covers video and podcast formats. That widens the tool beyond blog posts and academic papers.
文法: A free essay and paper checker sits outside the paid plan. Students use it for a quick pass before submitting academic work.
A free word counter handles length limits on the same page.
10. Platform Reach and Integrations
共同執筆者: It runs as a web app. You draft in the browser and paste finished text into your editor, which adds a step to the writing experience.
文法: The browser extension, desktop app, Grammarly mobile app and Grammarly keyboard cover most places you type. It is the most reliable option for working inside Google Docs and Microsoft Word without copy-pasting.
📌 注記： Grammarly publishes user trust guidelines covering how your text is handled. Release notes list new features and bug fixes so you can see what changed.
11. 価格設定とコスト
Here are the plans side by side.
| 計画レベル | 共著者 | 文法 |
|---|---|---|
| 無料 | ❌ トライアルのみ | 0米ドル |
| 入場料支払い済み | Pro: $11.99/month | Pro: $12 USD |
| 最高級 | Premium: $23.99/month | 法人向け：営業担当までお問い合わせください |
| プランの数 | 2 | 3 |
共同執筆者: Entry pricing is a few cents under Grammarly, but you must pay to use it at all. Premium at $23.99 buys unlimited completion suggestions and early access to new features.
文法: The free version does real work, so the paid tier is a choice rather than a gate. Enterprise pricing is quoted per team.
💡 プロのヒント: Run Grammarly free for two weeks first. If the only thing you miss is plagiarism detection, the $12 upgrade is an easy call.
さまざまなシナリオ
| 必要な場合は | 選ぶ | なぜ |
|---|---|---|
| Zero budget | 文法 | Free version with no word cap |
| First drafts written for you | 共著者 | Outline builder and full drafts |
| Correct spelling and grammar | 文法 | Dedicated grammar checker |
| IEEE academic citations | 共著者 | Format-specific citation generator |
| Writing help on your phone | 文法 | Mobile app and keyboard |
| 初心者向けのセットアップ | 文法 | Install once, works everywhere |
💰 あなたの予算
Grammarly costs nothing to start and stays useful at that price. CoWriter asks for $11.99 before you write a single letter.
🔌 あなたの技術スタック
If your work lives in Google Docs, Slack and email, Grammarly meets you there. CoWriter expects you to come to its web app.
📝 あなたの文章スタイル
Writers who value creativity and their own voice may find generated drafts flat. Grammarly leaves your sentences yours and only nudges them.
🎓 あなたの経験レベル
New writers learn faster with a tool that explains each correction. Grammarly gives that; CoWriter simply hands you finished stuff.
🆓 無料トライアルとデモ
Test both on one real project, for example a client article. That single test tells you more than any review.
🛟 サポートオプション
Grammarly has helpful docs used around the world and an active community. CoWriter support runs through email from your account.
切り替えガイド
Already paying for one of them? Here is what changes if you move.
🔄 Switching from CoWriter to Grammarly?
✅ 得られるもの：
- A real grammar checker with explanations
- A free version you can fall back on
- Support for multiple languages on mobile
❌ 失うもの：
- The outline builder for long articles
- IEEE-specific citation formatting
- The AI script generator
📋切り替え方法：
- Copy your saved drafts out of CoWriter
- 無料のGrammarlyアカウントを作成する
- Install the browser extension and paste your work in
🔄 Switching from Grammarly to CoWriter?
✅ 得られるもの：
- Full first drafts instead of edits
- An outline builder for long-form work
- Idea generation when you are stuck
❌ 失うもの：
- Live spelling and grammar feedback in every app
- 盗作チェッカー
- Mobile typing help on your phone
📋切り替え方法：
- Export documents from the Grammarly editor
- Start a CoWriter trial and pick a plan
- Rebuild your house style inside custom tones
私たちのレビューで取り上げられなかったこと
This comparison focused on solo writers, students and small content teams. We did not test enterprise rollouts, shared style guides across large teams, or either tool’s API. Our notes reflect the July 2026 versions of both products. If you manage fifty seats, your priorities will differ from what we covered here.
最終評決
| カテゴリ | 勝者 |
|---|---|
| 💰価格 | 文法 |
| ✍️ Draft Generation | 共著者 |
| 🔤 Grammar and Spelling | 文法 |
| 🎭 Tone and Style Control | 文法 |
| 📚 Academic Citations | 共著者 |
| 🔍 盗作検出 | 文法 |
| 🔌 プラットフォームリーチ | 文法 |
| 🏆総合優勝 | 文法 |
🏆 受賞者：GRAMMARLY
Grammarly wins 5 out of 7 categories.
最適な用途: daily editing, 学生 essays, business email, and anyone who wants mistake free text without paying first.
These are two different products aimed at two different moments. CoWriter is an ai powered drafting engine for people facing a deadline and an empty document.
Grammarly is an editing layer that sits on top of whatever you already wrote. Its ai assistance improves clarity, fixes errors and keeps your own voice intact.
CoWriter earns its place if you publish long articles weekly and need structure fast. The outline builder alone saves real hours.
For everyone else, Grammarly is the better first purchase. We hope this makes the choice simpler: pick CoWriter to produce words, and Grammarly to turn words into great writing.
More of CoWriter Compared
Here is how CoWriter measures up against nearby options:
共同執筆者対 ジェニー
CoWriter wins on: IEEE citation formatting, script generation for video, and per-project tone presets
ジェニが勝利した点： in-line autocomplete while you type, a usable free daily word allowance, and a larger source library
共同執筆者対 ライトソニック
CoWriter wins on: academic paper output, simpler two-plan pricing, and outline depth for long posts
Writesonicが勝利した点： short-form ad copy templates, bulk generation, and built-in publishing workflows
共同執筆者対 ペーパーパル
CoWriter wins on: generating drafts from scratch, idea prompts, and broader content formats beyond research
Paperpalが勝利した点： journal submission checks, a Microsoft Word add-in, and language editing built for non-native authors
Grammarlyの比較をもっと見る
Here is how Grammarly holds up against other writing software:
Grammarly vs クイルボット
Grammarlyが優れている点： app coverage without copy-pasting, explanations attached to each fix, and mobile keyboard support
QuillBotが勝利した点： paraphrasing modes, a cheaper paid tier, and a summarizer for long source documents
Grammarlyが優れている点： everyday 仕事 writing, a free tier with no word cap, and browser-wide availability
Paperpalが勝利した点： subject-specific academic phrasing, manuscript readiness reports, and journal formatting rules
Grammarly vs サイダー
Grammarlyが優れている点： depth of grammar correction, tone analysis, and plagiarism scanning
Siderが勝利した点： chatting with any web page, switching between several AI models, and summarizing videos
よくある質問
共同執筆者（cowriter）ですか、それとも共同執筆者（co writer）ですか？
The AI drafting tool at cowriter.ai is written as one word. A hyphenated “co-writer” usually means a human collaborator or a separate classroom accessibility app.
共同執筆者とはどのような仕事をする人ですか？
It generates article ideas, outlines and full drafts. Extra features include an IEEE citation generator, an AI script generator and custom style controls.
Cowriter AIは無料ですか？
No. There is a limited trial, then paid plans only. Pro costs $11.99 per month and Premium costs $23.99 per month.
共同執筆AIは優秀ですか？
It is strong for outlines and long-form first drafts. Output reads as machine written, so plan on editing every draft before you publish it.
完全に無料のAIライティングツールはありますか？
Grammarly’s free version is the closest. It covers unlimited grammar and spelling checks, though drafting and plagiarism detection need the paid plan.
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