Grammarly vs Claude for Email Writing in 2026: Best AI Email Assistant

Different Approaches to AI Email Writing

Grammarly and Claude serve different roles in email writing. Grammarly is a specialized writing assistant that fixes grammar, adjusts tone, and suggests improvements in real-time. Claude is a general-purpose AI that can draft complete emails from scratch, rewrite messages, and handle complex communication tasks. Understanding their strengths helps you choose the right tool — or use both.

Feature Comparison

Feature	Grammarly	Claude	Winner
Grammar & spelling	Industry-leading	Good but not specialized	Grammarly
Tone detection	Real-time tone meter	Understands but no meter	Grammarly
Email drafting	Short suggestions	Full email from context	Claude
Complex replies	Limited	Handles nuance well	Claude
Browser integration	Works everywhere	Web app only	Grammarly
Gmail integration	Native extension	Copy-paste required	Grammarly
Outlook integration	Native add-in	Copy-paste required	Grammarly
Rewriting	Sentence-level	Full email rewrite	Claude
Formality adjustment	Simple slider	Detailed instructions	Tie
Price	Free / $12 mo	Free / $20 mo	Grammarly

Grammar and Writing Quality

Grammarly is purpose-built for grammar checking and catches errors that general AI models miss. Its suggestions appear inline as you type, making it frictionless. Claude produces grammatically correct text but isn’t designed to check your existing writing in real-time.

Verdict: Grammarly for polishing your own writing; Claude for generating new text.

Email Drafting

Claude is superior for drafting emails from scratch. Give it context like “Write a follow-up email to a client who hasn’t responded to our proposal in two weeks. Be professional but persistent” and Claude produces a complete, nuanced email. Grammarly can suggest short phrases but doesn’t draft complete messages as effectively.

Handling Difficult Emails

Claude excels at sensitive communication: delivering bad news, negotiating, handling complaints, or writing diplomatically about disagreements. Its understanding of context and nuance produces emails that navigate complex interpersonal dynamics. Grammarly’s tone adjustment helps but doesn’t rewrite entire messages for diplomatic sensitivity.

Integration and Convenience

Grammarly’s biggest advantage is integration. It works directly in Gmail, Outlook, LinkedIn, and virtually any text field in your browser. You don’t need to switch apps or copy-paste. Claude requires opening a separate tab and copying text back and forth.

Best Workflow: Use Both

1. Draft with Claude — Provide context and get a complete email draft
2. Paste into Gmail/Outlook — Move the draft to your email client
3. Polish with Grammarly — Let Grammarly catch any grammar issues and fine-tune tone
4. Send — Confident in both content and correctness

Pricing Comparison

• Grammarly Free: Basic grammar and spelling — sufficient for most emails
• Grammarly Premium: $12/month — tone, clarity, formality adjustments
• Claude Free: Limited daily messages — enough for a few emails
• Claude Pro: $20/month — extended usage with Opus model

Our Recommendation

Choose Grammarly if you write your own emails and need real-time grammar/tone assistance. The browser extension makes it invisible and effortless.

Choose Claude if you need help drafting complex, sensitive, or high-stakes emails from scratch. Its contextual understanding produces better initial drafts.

Best value: Grammarly Free + Claude Free covers most email needs at no cost.