Grammarly

Grammarly is an AI writing assistant that catches grammar, spelling, punctuation, and style issues in real time. The free tier covers basic error correction; the Pro plan ($12/month annually) adds a plagiarism checker, advanced tone suggestions, and 2,000 AI prompts per month. Its strength is seamless integration — it works in your browser, Word, Google Docs, and a standalone desktop app.

What You Get

• Real-time grammar and spelling: Inline corrections appear as you type, across any text field in your browser or within native Word and Google Docs plugins.
• Style and clarity suggestions: Flags passive voice, wordiness, and overly complex sentences. A "Creative" intent setting relaxes some rules for fiction contexts.
• Plagiarism checker: Scans against 16 billion web pages. Available on Pro — useful for non-fiction research or academic work.
• Tone detection: Labels the emotional register of your writing (confident, formal, friendly, uncertain) — practical for query letters, blurbs, and newsletters.
• AI prompts: 100 per month on Free; 2,000 per month on Pro for sentence rewrites, brainstorming, and draft assistance. Each prompt processes up to 1,000 words.

Who It's For

• Authors who want passive background correction: Grammarly runs silently as you write without requiring separate editing sessions.
• Writers preparing manuscripts for professional editors: Clearing surface errors before hiring a copy editor can reduce per-word editing time and potentially lower costs.
• Indie authors producing marketing copy: The business-oriented style suggestions suit blurbs, email newsletters, and social media posts more than fiction prose.

Pricing: Free plan with basic grammar and 100 AI prompts/month. Pro costs $30/month billed monthly, $20/month billed quarterly, or $12/month billed annually ($144/year). Teams requiring more than 149 seats use a custom-priced Enterprise plan (no public rate). All Pro tiers include the same features — only billing cycle differs.

Strengths

• Wide integration footprint: Browser extension covers Gmail, social media, and most web-based writing tools. Word and Google Docs plugins require no copy-paste workflow.
• Mobile support: iOS and Android keyboard apps extend correction to mobile devices — no other major editing tool matches this.
• Low friction: Zero setup required per session. Useful for indie authors managing writing, publishing, and marketing in one workflow.

Limitations

• Biased toward business writing: Suggestions default to concise, formal prose. Grammarly regularly flags intentional fragments, unconventional punctuation, and stylistic choices that are standard in fiction. The "Creative" intent setting helps but doesn't resolve this.
• Shallow manuscript analysis: AI prompts handle only 1,000 words at a time, making full-novel structural review impossible. Grammarly does not produce style reports, repetition analysis, or pacing insights.
• Misses book publishing standards: Does not enforce Chicago Manual of Style conventions used in professional book editing. A human proofreader will catch what Grammarly misses.
• Not a substitute for human editing: Surface-level only. Developmental issues, consistency problems, and voice are outside its scope.

Alternatives

ProWritingAid offers deeper style analysis for book-length manuscripts with 25+ specialized reports and Scrivener integration. AutoCrit is focused on fiction prose patterns specifically. Neither has Grammarly's integration breadth or mobile support.