Best AI for Email Writing: 8 Tools to Draft Emails Faster
The average professional spends 28% of their workday on email. Much of that time goes to drafting replies, following up, and writing messages that could be handled in a fraction of the time with the right AI tool. But the market for AI email assistants has exploded — some tools write emails from scratch, others manage your inbox, and a few do both. For more details, check out our AI tools for academic writing. For more details, check out our AI resume builders. For more details, see our AI resume writers guide.
We tested eight AI tools that help with email writing, from general-purpose AI assistants like ChatGPT and Claude to dedicated email platforms like Superhuman and SaneBox. This guide covers what each tool does, what it costs, and which one is worth your money based on how you use email. See also: free AI writing tools. If you’re exploring options, check out our guide to AI for academic writing.
TL;DR: Top 3 Picks
- Superhuman AI — Best for high-volume email professionals. Auto Drafts writes follow-ups in your voice, Auto Labels sorts your inbox, and keyboard shortcuts make you genuinely faster. Starts at $25/month (annual).
- Claude — Best free/low-cost option for writing individual emails. Paste your context, describe the tone you want, and Claude drafts clean, professional emails without the filler other LLMs produce.
- Grammarly — Best for improving emails you have already drafted. Works inside Gmail and Outlook, catches tone issues, and rewrites sentences with a click. Pro starts at $12/month (annual).
Comparison Table
| Tool | Price | Best For | Works With | Rating |
|---|---|---|---|---|
| Superhuman AI | $25-$40/mo | Power email users, sales teams | Gmail, Outlook | 4.7/5 |
| Claude | Free / $20/mo | Drafting thoughtful emails | Any (copy-paste) | 4.6/5 |
| ChatGPT | Free / $20/mo | Quick drafts, brainstorming replies | Any (copy-paste) | 4.5/5 |
| Grammarly | Free / $12/mo | Editing and tone adjustment | Gmail, Outlook, web | 4.5/5 |
| Missive | Free / $14/user/mo | Team inbox collaboration | Gmail, Outlook, SMS | 4.4/5 |
| MailMaestro (Flowrite) | From $5/mo | Fast repetitive emails | Gmail, Outlook | 4.2/5 |
| Mailmeteor | Free / $9.99/mo | Personalized mass emails | Gmail, Google Sheets | 4.1/5 |
| SaneBox | $7-$36/mo | Inbox management and filtering | Any email provider | 4.3/5 |
Superhuman AI
What It Does
Superhuman is a premium email client that has gone all-in on AI. It replaces your default email app (Gmail or Outlook) with a faster, keyboard-driven interface built around speed. After being acquired by Grammarly in October 2025, Superhuman added a new wave of AI features: Auto Drafts that write follow-ups in your voice, Auto Labels that categorize every incoming email, and enhanced voice matching that adapts your writing style per recipient. For a deeper look, see our roundup of best AI writing tools.
Key Features
- Auto Drafts — AI automatically writes follow-up emails in your voice without prompting
- Auto Labels — Incoming emails are classified into categories (response needed, waiting on, meetings, marketing, cold pitches)
- Auto Archive — Marketing and cold emails are automatically archived
- Custom Auto Labels — Create AI-powered filters using natural language
- AI email rewriting — Write a blurb, then use commands like “shorten,” “lengthen,” “simplify,” or “improve writing”
- Voice learning — AI adapts writing style per recipient based on your email history
- AI search — Ask natural language questions about your inbox
- Split Inbox — Divide inbox into custom sections (Team, VIP, Google Docs)
- 100+ keyboard shortcuts — Users get through email 2x faster on average
- Auto-Send (optional) — AI can send emails on your behalf
Pricing
| Plan | Monthly | Annual (per month) | Key Additions |
|---|---|---|---|
| Starter | $30/mo | $25/mo | Core AI features, Split Inbox, Team Snippets |
| Business | $40/mo | $33/mo | Auto Drafts, Ask AI, Custom Auto Labels, CRM integration |
| Enterprise | Custom | Custom | SSO, dedicated support, advanced security |
Nonprofit/education pricing may be available at $10-$15/user/month (contact sales).
Pros and Cons
Pros:
– Auto Drafts are genuinely useful — the AI learns your voice well after a few weeks
– Keyboard-driven interface makes email processing measurably faster
– Auto Labels eliminates manual inbox sorting
– CRM integration (HubSpot, Salesforce) on Business plan is valuable for sales teams
Cons:
– At $25-$40/month, it is the most expensive option on this list
– Only works with Gmail and Outlook — no support for other email providers
– Learning the keyboard shortcuts takes time
– No free plan or trial — you commit from day one
Claude (Anthropic)
What It Does
Claude is not an email-specific tool, but its writing quality makes it one of the best AI assistants for drafting professional emails. You paste the context (the email you are replying to, the situation, the tone you want) and Claude produces clean, concise drafts. Its writing avoids the overenthusiastic filler that ChatGPT sometimes produces, which means less editing before you hit send.
Key Features
- Long context window (200K+ tokens) — paste entire email threads for accurate replies
- Tone flexibility — specify formal, casual, diplomatic, or direct and Claude adapts
- Projects — save email templates and instructions for recurring situations
- Artifact creation — Claude can format emails in a separate panel for easy copying
- Clean, professional writing style with minimal filler
- Works on web, iOS, and Android
Pricing
| Plan | Price | Key Features |
|---|---|---|
| Free | $0 | Basic access to Claude Sonnet |
| Pro | $20/month | Extended usage, Claude Opus, Projects |
Pros and Cons
Pros:
– Writing quality is the best among general-purpose AI for professional emails
– Long context window handles entire thread histories easily
– Projects feature lets you save instructions for recurring email types
– Free tier is sufficient for occasional email drafting
Cons:
– Not integrated into any email client — requires copy-paste
– No inbox management, scheduling, or tracking features
– No learning from your past emails (unlike Superhuman)
– Requires you to provide context manually each time
ChatGPT (OpenAI)
What It Does
ChatGPT is the most popular AI assistant and a common first choice for email drafting. With Custom GPTs, voice mode, and web search on paid plans, it is a flexible tool for quickly generating email drafts, brainstorming subject lines, and getting reply suggestions.
Key Features
- Custom GPTs — find or create GPTs specifically tuned for email writing
- Voice mode — dictate your email ideas and let ChatGPT draft them
- Web search — look up information to include in your emails (Plus and above)
- Multiple tones — request professional, casual, or any specific voice
- Templates — ask ChatGPT to create reusable email templates
Pricing
| Plan | Price | Key Features |
|---|---|---|
| Free | $0 | GPT-5.2 Instant (limited, ad-supported) |
| Go | $8/month | 10x free limits, file uploads |
| Plus | $20/month | GPT-5.2 Thinking, web search, ad-free |
Pros and Cons
Pros:
– Most flexible general-purpose option — handles any email scenario
– Custom GPTs for email are available in the GPT Store
– Voice mode is great for drafting while multitasking
– Largest user community with abundant email-writing prompts
Cons:
– Tends to write verbose, overly polite emails that need trimming
– Not integrated into email clients — requires copy-paste
– Free tier is ad-supported and limited
– No learning from your email history or voice
Grammarly
What It Does
Grammarly works differently from the other tools here. Rather than generating emails from scratch, it sits inside your email client (Gmail, Outlook, or any web-based editor) and improves what you write in real time. It catches grammar mistakes, adjusts tone, rewrites sentences, and offers AI-powered text generation through GrammarlyGO. For a deeper look, see our Grammarly vs ChatGPT comparison. For a deeper look, see our roundup of AI grammar checkers.
Key Features
- Real-time grammar and spelling correction inside your email client
- Tone detection that tells you how your message will come across
- GrammarlyGO — highlight text and say “make this more professional” or “shorten this”
- Full-sentence rewrites for better readability
- Reusable snippets for common email responses
- Plagiarism checker (useful for formal communications)
- Works in Gmail, Outlook, Slack, and 500,000+ other apps and websites
Pricing
| Plan | Monthly | Annual (per month) | Key Features |
|---|---|---|---|
| Free | $0 | $0 | Basic grammar, 100 AI prompts/month |
| Pro | $30/mo | $12/mo | Tone detection, 2,000 AI prompts, rewrites, plagiarism |
| Enterprise | Custom | Custom | Admin console, SSO, unlimited AI, brand tones |
Pros and Cons
Pros:
– Works directly inside Gmail and Outlook — no switching between apps
– Tone detection prevents you from sending emails that sound wrong
– GrammarlyGO rewrites are fast and usually on target
– The annual Pro plan at $12/month is affordable
Cons:
– Not designed to generate full emails from scratch — it is an editing layer
– Free tier AI prompts (100/month) run out fast
– Some suggestions push toward a casual tone that may not fit all contexts
– Browser extension can occasionally slow down email loading
Missive
What It Does
Missive is a collaborative inbox platform that unifies email, chat, SMS, WhatsApp, and social DMs in one workspace. Its AI features are powered by OpenAI integration (bring your own API key), and it generates drafts, summarizes threads, translates messages, and automates routing. Missive is built for teams, not individuals.
Key Features
- AI drafts and replies powered by OpenAI (BYOK model)
- Thread summarization for quickly catching up on long conversations
- Message translation for multilingual teams
- Shared inboxes for team email management
- Canned response embeddings — AI uses your saved responses as knowledge to draft replies
- AI-powered rules for automatic routing, labeling, and assignment
- Built-in team chat alongside email
- Integrations with Salesforce, HubSpot, ClickUp, Asana, Todoist, and more
Pricing
| Plan | Price | Key Features |
|---|---|---|
| Free | $0 (3 users) | 15 days message history |
| Productive | $14/user/month | Full history, shared inboxes |
| Business | Higher tier | Advanced analytics, automations |
AI usage costs are based on your OpenAI API key (pennies per use), not Missive’s pricing.
Pros and Cons
Pros:
– BYOK model means AI costs are transparent and cheap
– Team collaboration features (shared inboxes, internal chat) are excellent
– AI-powered rules automate repetitive inbox management
– Consolidates email, chat, SMS, and social in one tool
Cons:
– Designed for teams — overkill for individual users
– Free plan’s 15-day message history is very restrictive
– Setup complexity is higher than simple email tools
– Mobile app has some navigation issues
MailMaestro (formerly Flowrite)
What It Does
Flowrite was acquired by Maestro Labs in 2024 and merged into MailMaestro. The tool generates email drafts and replies from short instructions or bullet points. Type a few keywords describing what you want to say, select your tone, and MailMaestro writes a complete email. It integrates directly with Gmail and Outlook.
Key Features
- One-click draft generation from bullet points or short instructions
- Tone selector to control how the email sounds
- Smart template gallery covering common email types across roles
- Three reply suggestions for each incoming email
- AI email summary for long threads
- Inbox triage for prioritizing messages
- Gmail and Outlook integration
- Works in multiple languages
Pricing
MailMaestro (formerly Flowrite) pricing starts from $5/month for the basic plan, with higher tiers offering more features like inbox management and team collaboration.
Pros and Cons
Pros:
– Fastest way to generate emails from short notes
– Template gallery covers most common business email scenarios
– Tone selector is useful for matching different recipient expectations
– Affordable starting price
Cons:
– Limited to email only — no broader productivity features
– No inbox analytics or performance tracking
– The transition from Flowrite to MailMaestro has confused some users
– Quality of drafts varies with the complexity of your instructions. For more recommendations, see our list of AI productivity tools.
Mailmeteor
What It Does
Mailmeteor is a different kind of email tool. Rather than helping you draft individual emails, it specializes in sending personalized mass emails directly from Gmail. It works inside Google Sheets and Gmail, making each bulk email look like a personal, individually sent message. The AI features help generate cold email copy, subject lines, and replies.
Key Features
- Personalized mass emails that appear as individual messages
- AI-powered email generation for cold emails and subject lines
- Real-time open and click tracking
- BounceShield email verification to protect sender reputation
- Mail merge from Google Sheets — no external dashboard needed
- Scheduled sending and automated follow-ups
- CRM integration (Salesforce, HubSpot)
- Privacy-first: does not store or read your emails
Pricing
| Plan | Price | Emails/Month | Key Features |
|---|---|---|---|
| Free | $0 | 50/day | Basic personalization and reporting |
| Premium | $9.99/mo | 15,000 | Tracking, attachments, aliases |
| Pro | $24.99/mo | 45,000 | Follow-ups, automation, bounce detection |
| Business | $49.99/mo | 60,000 | Unlimited aliases, Zapier, priority support |
Lifetime plans are available starting at $199.99.
Pros and Cons
Pros:
– Works natively inside Gmail and Google Sheets — no learning curve
– Sends from your actual Gmail, maximizing deliverability
– BounceShield prevents wasted sends on invalid addresses
– Affordable starting price with a genuine free tier
Cons:
– Designed for outreach and campaigns, not individual email writing
– Subject to Gmail’s daily sending limits
– AI email generation is basic compared to ChatGPT or Claude
– Free tier’s 50 emails/day limit is restrictive for real campaigns
SaneBox
What It Does
SaneBox does not write emails — it manages your inbox using AI. It automatically sorts incoming emails into smart folders based on importance, provides follow-up reminders, snoozes messages for later, and offers a one-click unsubscribe feature. It works in the background with any email provider without requiring you to switch apps.
Key Features
- SaneLater — AI moves non-critical emails to a separate folder
- SaneBlackHole — One-click permanent unsubscribe (drag and forget)
- SaneReminders — Alerts you when expected replies have not arrived
- SaneNoReplies — Tracks sent emails that have not received responses
- Do Not Disturb — Pause incoming emails during focus time
- Email snoozing — Temporarily archive and resurface emails at a set time
- Daily Digest — Summary of unimportant emails
- Works with Gmail, Outlook, Apple Mail, Yahoo, and any IMAP client
- Only reads email headers (sender, subject, timestamp) — never message content
Pricing
| Plan | Monthly | Features |
|---|---|---|
| Snack | $7/mo | 1 email account, 2 features |
| Lunch | $12/mo | 2 accounts, 6 features each |
| Dinner | $36/mo | 4 accounts, all features |
14-day free trial available. 25% off for education, nonprofit, and government. Biannual billing brings costs down to $2.04/month for Snack.
Pros and Cons
Pros:
– Works with every email provider — no switching required
– Privacy-focused: only reads headers, never email content
– SOC 2 Type II certified
– After 1-2 weeks, reaches 98.5% accuracy in filtering
– Do Not Disturb and snooze features reduce email interruptions
Cons:
– Does not help with writing emails at all — strictly inbox management
– No free plan (14-day trial only)
– Requires 2-3 days of training before results improve
– Advanced features require the expensive Dinner plan
FAQ
Which AI tool actually writes the best emails?
For one-off professional emails, Claude produces the cleanest, most natural-sounding drafts. Superhuman AI writes the best automated drafts because it learns from your actual email history. ChatGPT is good for brainstorming but tends to be verbose. Grammarly does not generate emails from scratch but improves what you write.
Can AI email tools learn my writing style?
Superhuman AI explicitly learns your voice from past emails and adapts per recipient. Grammarly can save brand tones and snippets but does not learn automatically. Claude and ChatGPT can be prompted with style instructions but do not retain learning between sessions unless you use Projects (Claude) or Custom GPTs (ChatGPT).
Are AI-written emails detectable?
Most recipients cannot tell the difference if the email is well-edited. However, AI-generated text has patterns (certain phrase structures, predictable transitions) that trained detectors can flag. For sensitive communications, use AI to draft and then edit the output in your own voice. Tools like Grammarly that edit rather than generate are less detectable by nature.
What is the best free option for email writing?
Claude’s free tier provides the best writing quality for individual emails. Grammarly Free is useful for editing with 100 AI prompts per month. ChatGPT Free works but is ad-supported and limited. Mailmeteor Free handles up to 50 personalized emails per day if you need bulk sending.
Should I use a dedicated email AI or a general-purpose AI?
If you spend 2+ hours daily on email and want measurable time savings, a dedicated tool like Superhuman or Missive pays for itself. If you write fewer than 20 emails a day and mostly need help with wording, a general-purpose AI (Claude or ChatGPT) combined with Grammarly covers your needs at a lower cost.
Conclusion
The best AI email tool depends on your email volume and workflow:
- For high-volume professionals and sales teams: Superhuman AI ($25-$40/month) delivers the most automated experience with Auto Drafts, Auto Labels, and voice learning.
- For writing thoughtful individual emails: Claude (free or $20/month) produces the cleanest drafts with the least editing needed.
- For improving emails you write yourself: Grammarly Pro ($12/month annual) works inside your existing email client and catches problems before you send.
- For team email collaboration: Missive ($14/user/month) combines shared inboxes, AI drafts, and team chat in one platform.
- For inbox management: SaneBox ($7-$36/month) filters and organizes your email automatically without requiring you to switch apps.
Most people will get the best results by combining a writing tool (Claude or ChatGPT) with an editing tool (Grammarly) — a setup that costs $0-$32/month and covers the full email workflow.
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